NATO Non-nuclear Weapon State
Sharing U.S. Nuclear Weapons
Estimated Arsenal Size
- 40 U.S. non-strategic B-61 gravity bombs in two locations (20 at the Aviano Air Base, and 20 at the Ghedi Torre Air Base) 
- Non-strategic warheads: B-61-3, B-61-4 
- Delivery Aircraft: U.S. F-16C/D and Italian PA-200 Tornados
- The National Nuclear Security Administration (NNSA) is currently modernizing the non-strategic warheads deployed in Europe. NNSA is refurbishing and replacing components of the aging B-61-3 and B-61-4 warheads, converting them into the updated B61-12 model. Under NNSA’s B61-12 Life Extension Plan, the updated warheads will enter full production in 2020 and be deployed by 2024. 
- Italy plans to replace the PA-200 with the nuclear-capable F35-A Joint Strike Fighter from the United States, which will begin replacing existing NATO aircraft in 2024. 
- B-61-3: maximum yield of 170 kilotons
- B-61-4: maximum yield of 50 kilotons 
Nuclear Weapons Policies
- In the 2018 Brussels Summit, NATO reaffirmed that the fundamental purpose of NATO’s nuclear forces is deterrence, and that as long as nuclear weapons exist, NATO will remain a nuclear alliance. 
- Italy, as a NATO country hosting U.S. nuclear weapons, is not a signatory to the UN Treaty on the Prohibition of Nuclear Weapons (TPNW). 
- Unlike other NATO countries, Italy passed a resolution that allowed the Italian government to consider ratifying a ban on nuclear weapons. This suggests that the TPNW and NATO states are not necessarily incompatible. 
- State party to the NPT and PTBT. Signed and ratified the CTBT. 
 Hans M. Kristensen, “U.S. Nuclear Weapons in Europe,” Federation of American Scientists, November 2019, www.fas.org.
 Hans M. Kristensen, “Non-Strategic Nuclear Weapons, Special Report No 3,” Federation of American Scientists, May 2012, www.fas.org.
 United States Government Accountability Office, “NNSA Has a New Approach to Managing the B-61-12 Life Extension, but a Constrained Schedule and Other Risks Remain,” GAO-16-218, February 2016, pp. 10-25. www.gao.gov.
 Hans M. Kristensen and Robert S. Norris, “Slowing Nuclear Weapon Reductions and Endless Nuclear Weapons Modernizations: A Challenge to the NPT,” Bulletin of the Atomic Scientists 70, No. 3 (May/June 2014), pp. 96-108.
 Steve Andreasen et al, “Building a Safe, Secure, and Credible NATO Nuclear Posture,” NTI, January 2018.
 “NATO Summit Guide, Brussels 2018,” NATO, 11 July 2018, www.nato.int.
 “Positions on the treaty,” International Campaign to Abolish Nuclear Weapons, 7 July 2017, www.icanw.org.
 “Italian Parliament instructs Italy to explore possibility of joining the Nuclear Ban Treaty,” International Campaign to Abolish Nuclear Weapons, 20 September 2017, www.icanw.org.
 “Country Profiles: Italy,” Reaching Critical Will, accessed 8 July 2015, www.reachingcriticalwill.org; “Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space, and Under Water,” United Nations Office for Disarmament Affairs, accessed 8 July 2015, www.disarmament.un.org.
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Overview of the Nuclear Disarmament Resource Collection
View information and analysis of nuclear weapons disarmament proposals and progress worldwide, including detailed coverage of disarmament progress.
U.S. Nuclear Policies for a Safer World
NTI Co-Chairs Ernest J. Moniz and Sam Nunn call on the United States to resume a position of global leadership to reduce the risks posed by nuclear weapons.
Connecting the Pillars of the NPT: Multilateral Disarmament Verification and Non-Proliferation
To support full implementation of the NPT, it is crucial to find a way for non-nuclear weapon states to fulfill their obligation to contribute to disarmament without accessing nuclear weapons or knowledge of their designs, specific materials, or applied technologies.
- Non-nuclear weapon state (NNWS)
- Non-nuclear weapon state (NNWS): Under the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), NNWS are states that had not detonated a nuclear device prior to 1 January 1967, and who agree in joining the NPT to refrain from pursuing nuclear weapons (that is, all state parties to the NPT other than the United States, the Soviet Union/Russia, the United Kingdom, France, and China).
- The positioning of military forces – conventional and/or nuclear – in conjunction with military planning.
- North Atlantic Treaty Organization (NATO)
- The North Atlantic Treaty Organization is a military alliance that was formed in 1949 to help deter the Soviet Union from attacking Europe. The Alliance is based on the North Atlantic Treaty, which was signed in Washington on 4 April 1949. The treaty originally created an alliance of 10 European and two North American independent states, but today NATO has 28 members who have committed to maintaining and developing their defense capabilities, to consulting on issues of mutual security concern, and to the principle of collective self-defense. NATO is also engaged in out-of-area security operations, most notably in Afghanistan, where Alliance forces operate alongside other non-NATO countries as part of the International Security Assistance Force (ISAF). For additional information, see NATO.
- Kiloton: A term used to quantify the energy of a nuclear explosion that is equivalent to the explosion of 1,000 tons of trinitrotoluene (TNT) conventional explosive.
- The actions of a state or group of states to dissuade a potential adversary from initiating an attack or conflict through the credible threat of retaliation. To be effective, a deterrence strategy should demonstrate to an adversary that the costs of an attack would outweigh any potential gains. See entries for Extended deterrence and nuclear deterrence.
- Ratification: The implementation of the formal process established by a country to legally bind its government to a treaty, such as approval by a parliament. In the United States, treaty ratification requires approval by the president after he or she has received the advice and consent of two-thirds of the Senate. Following ratification, a country submits the requisite legal instrument to the treaty’s depository governments Procedures to ratify a treaty follow its signature.
See entries for Entry into force and Signature.
- Treaty on the Non-Proliferation of Nuclear Weapons (NPT)
- The NPT: Signed in 1968, the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) is the most widely adhered-to international security agreement. The “three pillars” of the NPT are nuclear disarmament, nonproliferation, and peaceful uses of nuclear energy. Article VI of the NPT commits states possessing nuclear weapons to negotiate in good faith toward halting the arms race and the complete elimination of nuclear weapons. The Treaty stipulates that non-nuclear-weapon states will not seek to acquire nuclear weapons, and will accept International Atomic Energy Agency safeguards on their nuclear activities, while nuclear weapon states commit not to transfer nuclear weapons to other states. All states have a right to the peaceful use of nuclear energy, and should assist one another in its development. The NPT provides for conferences of member states to review treaty implementation at five-year intervals. Initially of a 25-year duration, the NPT was extended indefinitely in 1995. For additional information, see the NPT.
- Partial Test Ban Treaty (PTBT)
- The PTBT: Also known as the Limited Test Ban Treaty (LTBT), the Treaty Banning Nuclear Weapons Tests in the Atmosphere, in Outer Space and Under Water prohibits nuclear weapons tests "or any other nuclear explosion" in the atmosphere, in outer space, and under water. While the treaty does not ban tests underground, it does prohibit nuclear explosions in this environment if they cause "radioactive debris to be present outside the territorial limits of the State under whose jurisdiction or control" the explosions were conducted. The treaty is of unlimited duration. For additional information, see the PTBT.
- Comprehensive Nuclear-Test-Ban Treaty (CTBT)
- The CTBT: Opened for signature in 1996 at the UN General Assembly, the CTBT prohibits all nuclear testing if it enters into force. The treaty establishes the Comprehensive Test Ban Treaty Organization (CTBTO) to ensure the implementation of its provisions and verify compliance through a global monitoring system upon entry into force. Pending the treaty’s entry into force, the Preparatory Commission of the CTBTO is charged with establishing the International Monitoring System (IMS) and promoting treaty ratifications. CTBT entry into force is contingent on ratification by 44 Annex II states. For additional information, see the CTBT.