United States Missile Overview

This page is part of the United States Country Profile.

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The United States has one of the most advanced missile arsenals in the world, deploying ballistic and cruise missiles across multiple platforms, which are armed with warheads for a variety of targets and applications.

The United States participates in numerous international efforts to limit missile proliferation, including the Missile Technology Control Regime and the Hague Code of Conduct Against Ballistic Missiles. At the bilateral level, Russia and the United States concluded the New START Treaty, limiting each country to 1,550 nuclear warheads on 700 deployed intercontinental ballistic missiles (ICBM), submarine launched ballistic missiles (SLBM), and strategic bombers. ¹ To counteract possible foreign missile threats, the United States is actively developing and deploying missile defense systems through the Obama Administration’s Phased Adaptive Approach (PAA).

The Missile Tables show the design characteristics for the most significant U.S. ballistic and cruise missiles.

Ballistic Missiles

The United States currently has two ICBMs and four battlefield short range ballistic missiles (BSRBM’s) that are deployed and operational. The LGM-30G Minuteman III (MM-III) is the only operational land-based ICBM in the U.S. arsenal. Although in service since 1970, the G model of the Minuteman III is a modern system, having undergone guidance system, propulsion system, and reentry vehicle replacements in recent years. The MM-III comes with two payload options, one with a single nuclear warhead, and the other with a multiple independently targetable reentry vehicle (MIRV), which carries three nuclear warheads. The 2010 U.S. Nuclear Posture Review stated that all ICBMs will be downgraded to carry a single nuclear warhead, but no implementation timeline has been established. ²

According to the New START Treaty’s September 2012 exchange of data between the United States and Russia, 450 Minuteman III’s are deployed and another 263 are listed as non-deployed. ³ The Twentieth Air Force, a unit of the Air Force Global Strike Command, is responsible for the U.S. land based ICBM arsenal. The 20th Air Force has three missile wings: the 90th Missile Wing at FE Warren Air Force Base (AFB), Wyoming; the 341st at Malmstrom AFB, Montana; and the 91st at Minot AFB, North Dakota. ⁴ Each missile wing maintains and operates Minuteman III ICBMs at its respective bases, where launch crews are on alert around the clock.

The second ICBM in the U.S. arsenal is the UGM-133A Trident II D5 (Trident II) submarine launched ballistic missile (SLBM). The United States deploys the Trident II on all 14 of its Ohio class submarines. Up to 12 submarines are operational at any given time, each capable of carrying 24 Trident II missiles, for a total of 288 missiles and 1,152 warheads. ⁵ According to the September 2012 New START data exchange, 239 Trident II’s are currently operational. ⁶ The missile, was designed to carry up to 14 warheads (shorter range configuration), but was limited to eight under the original START Treaty. ⁷ New START requirements may lead to a further reduction; however, the United States is not obligated to report the number of warheads per missile. ⁸

The Department of Defense has stated that it will not deploy more than 240 SLBM’s, and that it will reduce the carrying capacity of each Ohio-class submarine to 20 missiles each by 2015. ⁹

The Trident II will also be fitted on the Ohio Replacement submarines. The latter, whose production is slated to begin in 2021, will be fitted with 16 Trident II D5s, launching from 44-feet-long tubes, and is expected to stay in service until 2085. ^{10 11}

The United States currently fields four models of the BSRBM Army Tactical Missile System (ATACMS). The ATACMS missiles are battlefield weapons primarily intended for deep operations, and therefore do not have a strategic role.

Cruise Missiles

The United States has a vast arsenal of cruise missiles deployed throughout each of its military branches. The AGM-86B is the only nuclear-equipped cruise missile in the U.S. arsenal, currently deployed on the B-52H Stratofortress strategic bomber. The B-52H carries up to 20 cruise missiles-six externally on each wing pylon, and eight internally on a rotary launcher. ¹² According to New START counting rules, each bomber counts as one warhead, although it may carry up to twenty actual warheads. ¹³ In the September 2012 New START data exchange, the United States declared 78 deployed B-52Hs. ¹⁴

As with U.S. ICBMs, the Air Force Global Strike Command is responsible for the B-52H and the AGM-86B. The Air Force deploys the B-52H at Minot Air Force Base, North Dakota, and Barksdale Air Force Base, Louisiana; however, the Air Force no longer stores nuclear warheads at Barksdale. ¹⁵ Additional AGM-86B warheads are stored at Kirtland AFB, New Mexico, and Nellis AFB, Nevada. ¹⁶

The United States no longer has nuclear capable Tomahawk cruise missiles. The nuclear capable BGM-109A (TLAM-N) Tomahawk was removed from deployment in 1991, but remained in the U.S. stockpile. In the 2010 Nuclear Posture Review, the United States stated that all TLAM-Ns would be eliminated, a goal accomplished by March 2013. ¹⁷

Cruise missiles have shorter ranges, smaller payloads, and are slower than ballistic missiles. Their delivery is dependent upon a vehicle such as an air or naval vessel, which is vulnerable to air and coastal defenses. As a result, cruise missiles are widely seen as less than ideal strategic delivery systems. Cruise missiles however, are highly maneuverable, and follow a low, horizontal trajectory. This makes them less visible to enemy radar, and means no early-warning radar will detect their launch, making them possible first strike delivery systems.

The AGM-86B is only deployed in the continental United States, meaning the United States currently has no forward deployed nuclear cruise missiles. The voluntary U.S. retirement of the TLAM-N is viewed by many experts as a positive step towards future arms control talks with Russia concerning tactical nuclear weapons. The United States deploys numerous conventional cruise missiles, including the AGM-86C/D and the BGM-109E Tomahawk (TLAM-E).

Missile Defense

The U.S. missile defense plan, known as the Phased Adaptive Approach (PAA), is a four stage plan to develop and deploy missile defense assets in Europe and the United States. The PAA consists of four missile defense systems designed to engage ballistic missiles at various phases of flight. The Patriot system is the lower tier element, designed to engage short-range ballistic and cruise missiles within the atmosphere, and consists of the Patriot Advanced Capability (PAC) interceptor (MIM-104). The latest most advanced version, the PAC-3 (MIM-104F), utilizes a hit-to-kill warhead that requires a direct hit to destroy an incoming missile. The PAC-3 is carried on the M901 mobile launching station, which carries up to 16 PAC-3 interceptors. Some Patriot batteries deploy the PAC-2 (MIM-104E), which utilizes a burst fragmentation proximity warhead, and does not require the warhead to make direct contact with its target. PAC-2 launchers carry four interceptors. Patriot batteries are deployed by the U.S. military; numerous NATO allies such as Germany, Poland, and Turkey; and other allies including Japan, Israel, South Korea, Saudi Arabia, and the United Arab Emirates. ^{18 19}

The Terminal High Altitude Area Defense (THAAD) system comprises the next component of the BMD system. THAAD is a land based mobile system designed to intercept theater ballistic missiles at high altitudes during their terminal phase of flight. A THAAD battery consists of up to 6 launchers, each capable of carrying 8 missiles. ²⁰ Initially two THAAD batteries were deployed at Fort Bliss, TX, each with 3 launchers, for a total of 24 missiles. ²¹ In June 2009, the U.S. deployed a THAAD unit in Hawaii while the first THAAD unit was sent to Guam in April 2013 to counter the North Korean threat. ^{22 23 24} Secretary of State John Kerry affirmed in May 2015 the need for the U.S. to deploy, for the same reasons, THAAD systems in the Korean Peninsula. ²⁵ As of 2015 there are 5 deployed THAAD batteries, with 2 more ordered in 2014. ²⁶

The Ground Based Midcourse Defense (GMD) system is designed to engage IRBMs and ICBMS during their midcourse phase of flight. The GBI is launched from a silo, and has a range in excess of 5,000km. The United States currently deploys 30 GBIs at Fort Greely, AK (26 missiles), and Vandenberg AFB, CA (4 missiles). ²⁷ In 2015, the House of Representatives voted to add $30 million to the 2016 National Defense Authorization Act for the Missile Defense Agency. The funds would be used to add a third site for the Ground-based Midcourse Defense system (GMD), as well as to conduct additional testing, redesign the kill vehicle, and increase the number of interceptors from 30 to 44. ²⁸

The Aegis system is the sea-based component of the U.S. BMD system. The Aegis BMD engages short and intermediate range ballistic missiles during terminal (Standard Missile-2) or midcourse (Standard Missile-3) phases of flight. ²⁹ The United States deploys the Aegis BMD system on 26 ships (5 Ticonderoga class cruisers and 21 Arleigh Burke class destroyers). ³⁰ In 2015, Raytheon was awarded a $149.4 million contract for modification on SM-2s and full rate production on SM-6s. ³¹ The Standard Missile-6 (SM-6, RIM-174) replaced the SM-2 for sea-based terminal defense in 2014. ³²

1945 to 1957: World-War II to Sputnik

While a few U.S. individuals and the private sector had explored rocket technology since the early 1920s, a concerted government effort into ballistic missile research and development did not begin until 1944. At that time, the Army Ordnance Department signed a contract with General Electric (GE) to explore a variety of rocket and missile technologies, including solid and liquid propulsion systems, surface-to-air missiles (SAM), and surface-to-surface missiles (SSM). ³³ The Allies had been monitoring German missile development throughout the war, and the new Project HERMES examined the German Wasserfall SAM and the A-4 (V-2) ballistic missile. During the war, Nazi Germany fired over 3,000 A-4 missiles at Western Europe. ³⁴ The missile was highly inaccurate and useless as a tactical weapon. However, the A-4 affected Allied planning and defenses because it travelled at supersonic speed, provided no early warning of an attack, and did not risk German aircraft and personnel. The ability to deploy a weapon that did not risk lives or aircraft and was not susceptible to enemy defenses held great promise. This became especially true in the months and years following the war’s end, as the United States sought to demobilize and reduce troop numbers.

In the final days of the war, Allied forces occupied key missile sites, including the Mittelwerk Factory in Nordhausen, which contained over 250 A-4 missiles in various stages of production. ³⁵ In total, the United States captured 640 tons of equipment and components, and over 14 tons of rocket specific technical documents. ³⁶ With production equipment, missile components, and technical documents in hand, the United States recruited approximately 100 Germans into its missile program under Project Overcast/ Paperclip, a program designed to recruit German scientists and engineers into U.S. technical projects. ³⁷ By January 1946, with German scientist Werner Von Braun leading the effort, a full-scale program to assemble, launch, and improve on the German A-4 was underway at White Sands Missile Range in New Mexico.

Following the 1947 National Security Act, which established the U.S. Air Force as a separate branch of the military, the question of who should be in charge of rocket/missile development became hotly debated. The Army saw ballistic missiles as a field weapon-an extension of long range artillery-and therefore under its purview. The Air Force, charged with strategic bombardment, believed its mission would be constrained if the Army was solely in charge of missiles. The Navy, while not specifically arguing for a role, had developed expertise in liquid propellants, liquid engines, and rocket technologies through various programs from the late 1930s to the end of the war, and was developing a rocket to study the upper atmosphere to aid in weather prediction for the fleet. In the end, three separate rocket/missile programs developed. Von Braun’s team moved from White Sands to Huntsville, Alabama, where it continued to work for the Army Ballistic Missile Agency (ABMA), developing SRBMs based on A-4 technologies under the new Redstone project. The Air Force was tasked with developing an ICBM capability based on the previous MX-1593 project. Since the Navy was developing the Viking rocket to lift payloads into space, it was tasked with developing a satellite launch capability.

By 1954 ballistic missiles were a national priority. The Soviet Union, which tested its first atomic bomb in 1949, was actively developing a miniaturized nuclear warhead and a missile to carry it (the R-5), and was pursuing an ICBM capability (the R-7). In a January 1954 speech, Secretary of State John Foster Dulles stated that the United States must reinforce traditional defenses with a “deterrent of massive retaliatory” power. ³⁸ While Dulles did not specifically mention nuclear weapons, his meaning was clear-that nuclear weapons would deter the Soviet Union. As the Soviet Union made advancements in its missile program, the President’s Science Advisory Committee successfully recommended to President Eisenhower in February 1955 that ballistic missile development become a national priority. ³⁹ Von Braun’s ABMA team at Huntsville worked with the Navy and the Air Force to develop the Redstone missile into the Jupiter IRBM. The Air Force simultaneously worked on its own IRBM, Thor, while developing two ICBMs, Atlas and Titan. On 17 August 1957 the Soviet Union successfully tested the R-7 to a range of 6,000km, becoming the first country to develop an ICBM. ⁴⁰ Initially, U.S. policymakers did not believe Soviet claims; however, this changed when on 4 October 1957 the R-7 successfully launched a satellite, Sputnik, into space.

1957 to 1969: Space Race, Nuclear Arms Race, and the Beginning of Arms Control

Following Sputnik’s launch, the United States raced to counter the new Soviet ICBM capability. The THOR IRBM was deemed operational, and in June 1958 the United States signed an agreement to deploy the missile in the United Kingdom. Throughout 1958 and 1959 the United States continued to test Thor, Jupiter, Atlas, and the new Navy Polaris missiles. All four missiles became operational by 1960. However, Sputnik and the Soviet ICBM had created the widespread perception in the United States of a missile gap between the United States and the USSR, which became a major theme in the 1960 Presidential race. Successful recovery of film canisters from the new Corona satellites in late 1961 proved that the missile gap did not exist; however, this information could not be shared with the public. For the remainder of the decade, the United States government focused on the space race and beating the Soviets to the moon, a goal accomplished in 1969.

As the public focused on the space race, U.S. officials continued to develop and deploy new missile systems. Events such as the Cuban Missile Crisis and the outbreak of the Vietnam War further fueled the nuclear arms race. The U.S. nuclear arsenal peaked between 1965 and 1967, with over 30,000 nuclear weapons in the U.S. stockpile, deployed on over 1,000 ICBMs, 600 SLBMs, and strategic bombers. ⁴¹

However, the 1960s also marked the beginning of U.S.-Soviet arms control. Despite increased tensions between the United States and the USSR, events such as the 1962 U.S. Project Fishbowl atmospheric test series and the Cuban Missile Crisis facilitated negotiation of a limited test ban. The Starfish Prime test added electrons to the Van Allen belt, disrupted communications across the Pacific, disabled six satellites in low earth orbit (LEO), and knocked out electricity in parts of Hawaii. A booster failure on the Thor missile during the Bluegill Triple Prime test led the range safety officer to blow up the missile shortly after liftoff, causing radioactive debris to fall back on the launch site. ⁴² The Cuban Missile Crisis magnified the danger of nuclear weapons by displaying how close the two nations were to nuclear war. Events brought the parties back to the negotiating table, and in 1963 the United States, the United Kingdom, and the Soviet Union concluded the Partial Nuclear Test Ban Treaty (PTBT), banning nuclear weapon tests and “other nuclear explosions” in the atmosphere, outer space, and underwater

1967 to 1993: Cooperative Restraint and Arms Control

Seven days after the signing of the PTBT, the UN General Assembly accepted resolutions from the United States and the Soviet Union calling for a ban on weapons in space. Advances in rocketry and space technology had opened up the possibility of deploying nuclear weapons in space; however, advances in satellite technology, ranging from communications to image intelligence, and the promise of manned space exploration, offered competing possibilities for the use of space. The weaponization of space would likely lead to long-lasting debris fields that would inhibit the use of space indefinitely for civilian and intelligence support. To preserve space and the benefits that satellite technology offered, the United States and the Soviet Union signed the Outer Space Treaty (OST) in January 1967, prohibiting placement of WMD in space, in orbit, or on celestial bodies, including the moon. ⁴³ The treaty further reserved space “for all mankind,” and classified astronauts as envoys of all mankind. ⁴⁴

Progress in U.S. missile technology continued in the early 1970s with the development of the Multiple Independently Targetable Reentry Vehicle (MIRV). The U.S. first deployed MIRV’ed ICBMs in 1970 on the Minuteman III, and on SLBMs in 1971 on the Poseidon. ⁴⁵ MIRVs enabled a single ballistic missile to carry multiple warheads, so that it could be used against multiple major targets. This significantly enhanced the U.S. first strike capability, improving the likelihood it could destroy a majority of Soviet strategic forces and military bases (as such, it also destabilized the deterrence concept underlying Mutually Assured Destruction). Between 1969 and 1979 the total number of SLBMs and ICBMs in the U.S. arsenal remained near 1,700, but the total number of warheads deployed on U.S. missiles increased from 2,500 to 7,500. ⁴⁶

From 1969 on, the United States and the Soviet Union negotiated a number of arms treaties first capping, and later reducing the number of deployed ICBMs/SLBMs and nuclear warheads. Since the first arms control treaty, the counting of delivery systems has been the primary means of limiting and reducing strategic arsenals.

Between November 1969 and May 1972, the United States and Soviet Union met to discuss limiting strategic offensive and defensive weapons systems in the Strategic Arms Limitation Talks (SALT-1). Asymmetries in the U.S. and Soviet arsenals at the time complicated negotiations. In 1972, the USSR deployed approximately 300 more ICBMs/SLBMs than the United States; however, the United States, with MIRV’ed missiles, had double the warheads of the Soviet Union. ⁴⁷ The Soviet Union countered these warhead asymmetries by producing missiles with higher throw weights capable of carrying larger payloads. By 1970, each country had robust missile arsenals deployed across its territory and on submarines throughout the Atlantic and Pacific Oceans. Given this high ballistic missile saturation, both sides began developing anti-ballistic missile defense (ABM) systems.

SALT-I talks resulted in two agreements in 1972, the Anti-Ballistic Missile Treaty (ABM Treaty), and the Interim Agreement on Offensive Arms. The ABM Treaty limited each country to fielding two fixed, ground based ABM systems, one around each country’s capital, and one around a non-specific ICBM silo base. ⁴⁸ The Interim Agreement capped the number of ICBMs and SLBMs on both sides at their current levels as of 1 July 1972. ⁴⁹ The inequality in missile and warhead numbers and capabilities posed problems for both governments, and the Interim Agreement was seen as a stepping stone that each country agreed to abide by until a more comprehensive agreement could be reached.

The United States and the Soviet Union signed the Strategic Arms Limitation Talks II (SALT II) treaty in June 1979, which addressed strategic nuclear delivery systems by capping the number of ICBMs, SLBMs, and strategic bombers, and limiting the permissible number of MIRV’ed vehicles. The United States never ratified the treaty due to the December 1979 Soviet invasion of Afghanistan; however each country agreed to abide by the treaty’s limits nevertheless.

In the 1950s and 1960s, the United States actively researched, developed, and deployed new missile systems. By the early 1970s, however, the United States had developed the Minuteman III ICBM, which satisfied its strategic requirements for the land-based leg of the nuclear triad. Since 1970 the U.S. has only developed one new ICBM, the Peacekeeper (LGM-118A; MX). The MX is no longer operational, and today the U.S. strategic arsenal consists solely of modified Minuteman IIIs. Washington continued to improve its SLBMs. In the 1960s it deployed various versions of the Polaris (UGM-27) SLBM, and in 1971 the USS James Madison became the first submarine to deploy the Poseidon (UGM-73). The Poseidon did not meet strategic requirements due to its limited range of 4,630km; in 1979, the United States remedied this limitation by deploying its first SLBM with ICBM range, the Trident I C4 (UGM-93A). The Trident I had a range of 7,400km, and was replaced by the current Trident II in the early 1990s.

In the mid-1970s the Soviet Union developed and deployed the RSD-10 “Pioneer” (NATO: SS-20 Saber and SS-28 Saber II), a road mobile nuclear IRBM. The missile significantly upgraded the USSR’s ability to strike Western European and NATO targets. NATO immediately responded with a “two track” program to negotiate with the Soviets to eliminate such weapons, while simultaneously developing its own intermediate range capability should negotiations fail. ⁵⁰

Negotiations began in 1980, but they ceased in 1983 when NATO deployed Pershing II IRBMs and BGM-109Gs (Tomahawk ground launch cruise missile GLCM) in Europe. Talks resumed in January 1985, with both sides signing the Intermediate Nuclear Forces (INF) Treaty in December 1987. The treaty eliminated all ground based short and intermediate range missiles worldwide (ranges of 500-5,500km), and entered into force on June 1, 1988. ⁵¹

On 16 April 1987 the United States, Canada, France, Germany, Italy, Japan, and the United Kingdom established the Missile Technology Control Regime (MTCR). The MTCR is a voluntary agreement designed to limit the export of missile systems and critical technologies. The regime calls on members to show restraint in transferring missiles, and particularly any technologies and equipment that could help a country produce a missile with a range of 300km or more, and/or capable of carrying a 500kg warhead.

Although the INF Treaty eliminated an entire class of weapons, the U.S. and the USSR continued to deploy ICBMs and SLBMs in large numbers throughout the Cold War. With its signature in July 1991, the Strategic Arms Reduction Treaty (START I) placed limits on the number of missile launchers and warheads. Negotiations on START-II and later START-III occurred throughout the 1990s; however, neither treaty entered into force.

2001 to the Present: Missile Defense and New START

In November 2002 the United States adopted the Hague Code of Conduct against Ballistic Missile Proliferation (HCOC), which supplements the MTCR. While not a treaty, the HCOC strengthened the MTCR by establishing binding commitments to stem the proliferation of ballistic missiles. The HCOC requires members to report their ballistic missile activities, including by notifying signatories prior to conducting tests. ⁵²

In November 2001 President George W. Bush announced that the United States would unilaterally reduce its strategic arsenal to between 1,700 and 2,200 warheads within a decade. ⁵³ Russian President Vladimir Putin responded by requesting a formal arms control framework for bilateral reductions. The Strategic Offensive Reductions Treaty (SORT) was signed in March 2002, and entered into force in June 2003. Unlike previous treaties, SORT did not limit delivery vehicles.

On 13 December 2001 President Bush gave formal notice to Russia that the United States was withdrawing from the 1972 Anti-Ballistic Missile (ABM) Treaty. The ABM Treaty had an “unlimited duration,” but allowed for either the United States or Russia to withdraw if “extraordinary events related to the subject matter of [the] Treaty” jeopardized either nation’s supreme interests. ⁵⁴ In his speech, President Bush justified U.S. withdrawal by stating that, “[T]he events of September the 11th made all too clear, the greatest threats to both our countries come not from each other, or other big powers in the world, but from terrorists who strike without warning, or rogue states who seek weapons of mass destruction.” ⁵⁵

In December 2002 President Bush announced the National Missile Defense Initiative, a plan calling for the deployment of 20 GBIs in Alaska and California, and 20 sea-based systems on three Navy vessels by 2004. ⁵⁶ Additionally, the Bush administration released National Security Presidential Directive 23, which called for missile defenses to protect “the United States, its deployed forces, and its allies.” ⁵⁷ The defense plan was to utilize Patriot systems, ground and sea based interceptors, and ground, sea, and space based radar and sensors. In summer 2006 the Missile Defense Agency (MDA) conducted formal studies of sites in Poland and the Czech Republic for staging missile defense components. The Bush administration had been in talks with each government since 2001, and in May 2006 the Czech government formally requested that the United States consider basing radar stations in the Czech Republic. ⁵⁸

In 2001 Russian President Vladimir Putin had stated that the U.S. missile defense plan did not pose a threat to Russia; however, the planned basing of a system in Central or Eastern Europe changed Russian views. ⁵⁹ Putin announced on the eve of a G-8 summit in Moscow that Russia would retaliate by targeting European cities with its missiles. ⁶⁰ Putin followed up by recommending that the United States field radar sites in Azerbaijan, Turkey, Iraq, or at sea, rather than in Central or Eastern Europe. ⁶¹ However, the United States reached preliminary agreements with both Poland and the Czech Republic in 2008 for radar sites, pending ratification by both governments. ⁶² One month prior to U.S. elections, in October 2008, the Czech Republic announced that it was putting the process on hold until the next President assumed office. Poland followed suit after the election in November 2008. ⁶³

Following his inauguration in January 2009, President Obama announced that his administration would support missile defense, but did not elaborate any specifics. In September 2009, the Obama administration officially cancelled President Bush’s missile defense plan, and announced a new Phased Adaptive Approach (PAA) to missile defense in Europe. The PAA called for the deployment of missile defense systems in four phases: ⁶⁴

• Phase One (in the 2011 timeframe) – Deploy current and proven missile defense systems available in the next two years, including the sea-based Aegis Weapon System, the SM-3 interceptor (Block IA), and sensors such as the forward-based Army Navy/Transportable Radar Surveillance system (AN/TPY-2), to address regional ballistic missile threats to Europe and our deployed personnel and their families;
• Phase Two (in the 2015 timeframe) – After appropriate testing, deploy a more capable version of the SM-3 interceptor (Block IB) in both sea- and land-based configurations, and more advanced sensors, to expand the defended area against short- and medium-range missile threats;
• Phase Three (in the 2018 timeframe) – After development and testing are complete, deploy the more advanced SM-3 Block IIA variant currently under development, to counter short-, medium-, and intermediate-range missile threats;
• Phase Four (in the 2020 timeframe) – After development and testing are complete, deploy the SM-3 Block IIB to help better cope with medium- and intermediate-range missiles and the potential future ICBM threat to the United States.

In 2011 Phase One was completed when the first BMD capable ship, the USS Monterey, was deployed to the Mediterranean Sea, and the first AN/TPY-2 X-band radar was deployed in Turkey. The United States signed an agreement with Romania to host a land-based SM-3 interceptor site in 2015 for Phase Two; the missiles will be deployed at a military base in Deveselu. Phase Three includes a similar agreement with Poland to host an SM-3 site by 2018. Phase Four called for the development of a new model of the SM-3 interceptor to be deployed; however, no proposals for its deployment were made. ⁶⁵

In April 2010 the United States and Russia signed the New START Treaty as a replacement to SORT, which entered into force in February 2011. The treaty returned to the previous arms control standard of focusing on the number of allowable ICBMs, SLBMs, and strategic bombers in each arsenal, while also limiting the number of deployed warheads for all strategic systems. The treaty also acknowledged the interrelationship between offensive and defensive missiles; however, it did not put any missile defense obligations or limits on either country. Russia has stated that its interpretation of the agreement leaves open the possibility to withdraw from the treaty should the United States increase its missile defense capabilities in a way that threatens Russian national security. ⁶⁶

In January 2015, the U.S. Air Force awarded the Northrop Group a $963.5 million contract for support of the Minuteman III intercontinental ballistic missile ground subsystems; in May 2015, the group was also awarded a $99 million contract for nuclear safety checks on Minuteman III hardware and software. ^{67 68}

The Ohio class SSBN’s have a service life of 42 years and will begin retiring at a rate of one ship per year beginning in 2027. The Navy’s Trident II Life Extension Program will sustain, update, or replace each Trident II through 2042, two years after the last Ohio class SSBN is retired. The Navy plans to replace the Ohio class SSBN with the SSBN(X). The FY2013 budget includes $564.9 million for research and development on the SSBN(X), and extends the procurement date of the first ship to 2021. ⁶⁹ The first SSBN(X) will enter into service in 2030, with the final, twelfth ship, entering service in 2042. ⁷⁰ The SSBN(X) will include 16 missile launch tubes, and will initially carry the Trident II until a replacement missile is developed. ⁷¹ There are currently no plans or programs to replace the Trident II.

In the 2001 Nuclear Posture Review, the George W. Bush administration expressed interest in integrating long-range precision conventional weapons into the strategic nuclear forces. ⁷² The concept, identified as Prompt Global Strike, called for the ability to strike targets anywhere in the world in under an hour without relying on forward deployed forces. Initially, the Navy and the Air Force were responsible for developing a PGS system. The Navy pursued two avenues for a submarine launched PGS capability. One called for a conventionally armed Trident II SLBM, while the other sought to develop a conventional submarine launched intermediate range ballistic missile (SLIRBM). Each program was cancelled; however, in 2012 the Pentagon reaffirmed its interest in a submarine launched PGS weapon. ⁷³ The Air Force, in conjunction with the Defense Advanced Research Projects Agency (DARPA), conducted the FALCON study, which called for the development of a hypersonic delivery vehicle called the Common Aero Vehicle (CAV), to be delivered from either an ICBM or an aircraft. ⁷⁴ FALCON outlined a number of objectives that a PGS system would have to meet, including range requirements, alert status, and intelligence, surveillance, and reconnaissance (ISR) capabilities. The FALCON study was terminated in 2008.

In 2008 Congress appropriated $100 million to the Conventional Prompt Global Strike program with two stipulations; first, the funds could not be used for the Navy’s Trident program, and second, a portion of the funds had to be allocated to the Army’s hypersonic boost-glide vehicle. ⁷⁵ Since 2008 the Army has received additional funds for the Advanced Hypersonic Weapon (AHW), including $91 million in 2012 and $42 million in 2013. ⁷⁶ The Army conducted the first test of the AHW in November 2011. The AHW was launched from a booster rocket derived from the Polaris ballistic missile, and landed 3,999 km away in the Kwajalein Atoll. ⁷⁷

The Air Force and DARPA have received over $300 million since 2008 to follow up their FALCON study and CAV concept with their own hypersonic glide vehicle. The HTV-2 was tested in 2010 and 2011, with each flight ending prematurely. While the Army and Air Force/DARPA programs emphasize glide payload delivery vehicles (PDV), the Air Force Conventional Strike Missile (CSM) program focuses on a land-based boost vehicle to launch the PDV. Currently the CSM calls for a Minotaur IV rocket, a modified Peacekeeper missile, to launch the PDV. The Minotaur IV follows a lower trajectory than most ballistic missiles to help mitigate the risk of a launch being mistaken for a nuclear ballistic missile launch. The Minotaur IV is scheduled to be ready for deployment by 2015; however, a PDV for the rocket is further away. DOD has stated that a decision on the PDV will not be made until the technologies have proven successful in a minimum of five demonstration flights. ⁷⁸

Outside of the CPGS program, the Air Force, Navy, DARPA, and NASA are developing scramjet technologies that could serve as PGS delivery vehicles. A scramjet is a ramjet cruise engine that operates at supersonic speeds. The Air Force has developed an experimental vehicle, the X-51 Wave Rider, which uses scramjet technologies. After a first failed flight test in May 2010, the X-51 underwent a successful test in 2013, flying at 60,000 feet altitude and almost 4,000 mph before running out of fuel. ⁷⁹ As a result, DARPA is working to commission the first plane by 2023 and using the technology for missile systems by 2020. ⁸⁰ The X-51, and scramjet technologies, are in the early stages of development, and will not likely contribute to PGS missions in the near future. However, a scramjet vehicle such as the X-51 would not leave the earth’s atmosphere or follow a ballistic trajectory, making it a possible candidate for a long-term solution to the PGS mission.

In March 2013 the United States entered into an austere fiscal policy known as sequestration, cutting expenditures across the government in an effort to decrease the deficit by up to $1.2 trillion. As a consequence of budget cuts, the Obama administration cut the Tomahawk missile program by $128 million for fiscal year 2015; the program is set to be entirely eliminated by 2016. In addition, the new budgetary restrictions have led the Navy to abandon its hellfire missile procurement. ⁸¹

Nevertheless, on 16 March 2013 the Obama administration, in light of North Korean rocket tests, announced that the United States was adding 14 ground based interceptors to the GMD system. ⁸² All fourteen interceptors will be based at Fort Greely, Alaska and will be online by September 2017. ⁸³ The administration further announced that it was scrapping Phase IV of the Phased Adaptive Approach. Proponents of Phase IV, which was designed to defend against launches from the Middle East and Iran, have noted that this may leave the United States, and particularly the East Coast, vulnerable to attacks from the region in the near future. U.S. lawmakers have called on Secretary of Defense Chuck Hagel to include $250 million in his pending 2014 budget request to pursue missile defense options on the East Coast. ⁸⁴

On 3 April 2013 the United States announced that it was sending a THAAD battery to Guam to strengthen regional missile capabilities. ⁸⁵ The announcement came after North Korea’s December 2012 rocket test, a February nuclear test, the cancellation of the 1953 Korean War armistice, and subsequent announcements that the North Korean military has received approval for a nuclear strike on the United States. Although North Korea does not possess a nuclear capable ICBM, and iis currently unlikely to be able to fit a nuclear warhead on a missile, the DPRK does possess medium range missiles that can reach U.S. allies and assets in the region. The U.S. did not announce when the THAAD system would be operational, or how long the deployment would last. The THAAD deployment includes self-propelled launchers, interceptor missiles, radar and fire-control systems, and 95 Army personnel. ⁸⁶