Dismantle Bombs, Not Treaties
In October 2012, David Johnson, a former nuclear weapons specialist at the U.S. Pantex Plant, witnessed the dismantlement of the last B53 nuclear bomb—at one point the most destructive weapon in the U.S. arsenal. Johnson, who had worked to develop the weapon, described the moment as “[coming] full circle” saying, “I consider myself privileged to work on [the bomb] and then help retire it.”  The Clinton Administration retired the B53 in 1997, but dismantling the last B53 took fifteen years.
During the 1990s, the U.S. typically dismantled more than 1,000 nuclear weapons per year. But in recent decades, dismantlement rates have fallen. In January 2017, then-Vice President Joe Biden announced that there were still 2,800 nuclear weapons awaiting dismantlement—a backlog that, at current rates, would take until 2026 to clear.  Dismantlement rates have fallen, in part, because resources have shifted to maintenance and more comprehensive life-extension programs for existing warheads.
For example, while the Obama Administration had planned to retire several hundred B83 warheads in the 2020s – adding to the dismantlement queue – the Trump Administration, in its 2018 Nuclear Posture Review, reversed this decision and announced that the United States would sustain the B83 past its previously planned retirement date. 
You too can #DismantleBombsNotTreaties by taking a picture of yourself taking apart the below 3D bomb in augmented reality. Share your image on Twitter with @NTI_WMD using #DismantleBombsNotTreaties. Read how to access the augmented reality from your mobile device or watch the instructional video.
The 2018 Nuclear Posture Review reversed plans to retire the B83 gravity bomb. View the annotated assembled and disassembled B83 gravity bomb graphics.
During the Cold War, in 1967, the U.S. nuclear arsenal peaked at 31,255 warheads and bombs while the Soviet arsenal peaked at 40,159 nuclear warheads and bombs in 1986.  These stockpiles started coming down as the United States and the Soviet Union began negotiating a series of arms control treaties – first, limitations aimed at capping the number of deployed nuclear weapons and delivery systems, and then agreements aimed at reducing them.
These treaties included the Intermediate-Range Nuclear Forces (INF) Treaty (1987), the 1991 Strategic Arms Reduction Treaty (START), and the 2011 New Strategic Arms Reduction Treaty (New START), which is set to expire in 2021. Along with voluntary measures such as the Presidential Nuclear Initiatives, these treaties have led to a large number of excess non-deployed nuclear warheads that Russia and the United States have chosen to dismantle.
According to declassified data, between 1994 and 2017 alone, the United States dismantled almost 11,000 nuclear weapons.  Additionally, under the Megatons to Megawatts program, which was implemented from 1993 to 2013, the United States purchased weapons-grade fissile material from Russia and converted it into fuel for civil nuclear power plants across the United States. Over the lifespan of Megatons to Megawatts, approximately 500 tons of weapons-grade highly enriched uranium (HEU) were removed from Soviet-era warheads and recycled into 14,000 tons of reactor fuel—ensuring that they could never be used for weapons.  The United States and Russia today possess a fraction of their Cold War nuclear arsenals and fissile material. Today, Russia has approximately 4,490 warheads, while the United States has approximately 3,800. 
However, continued progress on nuclear arms limitation and reduction is at risk. On 2 August 2019, the United States officially withdrew from the INF Treaty, in response to Russia’s violations of that Treaty. The INF Treaty was a Cold War-era agreement between the United States and Russia that eliminated land-based nuclear-capable ballistic and cruise missiles with a 500-5,500km range.  With the INF Treaty gone, New START is the only remaining agreement limiting U.S. and Russian nuclear arsenals. It will expire in February 2021, unless the United States and Russia agree to extend it for another five years. Formal discussions on extension have yet to begin. Additionally, due to complications from the Coronavirus pandemic, important discussions on the status of global arms control treaties, such as the 2020 Review Conference of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), have been postponed.  Similar delays could push New START extension discussions even closer to the treaty’s 2021 expiration date.
If New START is not extended, there would be no legally binding restraints on U.S. and Russian nuclear forces. In that scenario, each side might be impelled to grow, rather than reduce, its nuclear arsenals.
There is a safer course. The United States and Russia could end the uncertainty over the fate of New START and extend the treaty for an additional five years before it expires in 2021.  If the United States and Russia let New START expire in 2021, it will mark the first time since 1972 without legally binding limits on the two largest nuclear arsenals in the world. Those limits are backed with extensive verification measures that build confidence, predictability, and stability.
By the end of the Cold War, both countries had come to understand that arms control provided limits, verification, and security mechanisms necessary for a safer world. That remains as true today as it was then. Extending New START is a crucial step to maintain strategic stability and a necessary foundation for additional steps to further constrain nuclear competition. The United States and Russia must sustain their efforts to reduce nuclear arms and dismantle excess nuclear weapons. Like David Johnson, they too, can come full circle.
 “‘Last of the Big Dogs’ B53 Nuclear Bomb Dismantled at Pantex,” Pantexan (Winter 2012), pp. 4-5. https://pantex.energy.gov.
 Hans M. Kristensen, “Obama Administration Announces Unilateral Nuclear Weapon Cuts,” Federation of American Scientists, 11 January 2017, https://fas.org.
 Stephen Young, “The Trump Administration’s Dangerous New Nuclear Policy,” Union of Concerned Scientists, 12 January 2018, allthingsnuclear.org.
 Hans M. Kristensen and Matt Korda, “Nuclear Notebook: Nuclear Arsenals of the World,” Bulletin of the Atomic Scientists, https://thebulletin.org.
 See here for data declassified by the Obama Administration: https://open.defense.gov. The Trump Administration has not disclosed stockpile and dismantlement numbers for 2018.
 “Megatons to Megawatts,” Centrus Energy, www.centrusenergy.com.
 “New START Treaty,” U.S. Department of State, www.state.gov.
 James J. Cameron, “The U.S. officially withdrew from the INF Treaty. Here’s what you need to know,” The Washington Post, 3 August 2019, www.washingtonpost.com.
 Daryl Kimball, “NPT Review Conference Postponed,” Arms Control Association, April 2020, www.armscontrol.org.
 Shervin Taheran, “New START Extension Debated,” Arms Control Association, April 2019, www.armscontrol.org.
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