By Air Marshal Anil Chopra (r)
An unreliable American nuclear umbrella means more countries want the nuclear bomb. For long, Europe and some other Asian countries were banking on US security guarantees. Ukraine had denounced nuclear weapons after the Soviet Union imploded, but after the Russian invasion of February 2022, and Russian threats to use a tactical nuclear weapon, Ukraine is repenting that decision. Poland and South Korea are among the countries that have expressed interest in nuclear weapons on their soil. There are others in Europe who want a formal nuclear umbrella. Highly threatened Iran has been clandestinely pursuing a nuclear weapons program with the hope that one day it will be able to stand up to the American and Israeli threats and sanctions. Could this start another round of nuclear proliferation?
Ukraine Nuclear Weapons Denunciation
In 1990, after Ukraine’s “Declaration of Sovereignty”, they pledged not to acquire, produce, or accept nuclear weapons. In 1991, Ukraine declared itself a non-nuclear-weapon state. In 1994, Ukraine agreed to give up over 1,700 Soviet nuclear weapons in exchange for security assurances from Russia. There is the ICAN (International Campaign to Abolish Nuclear Weapons) that condemns all threats to use nuclear weapons, regardless of the circumstances. Ukraine has accused Russia of violating the 1994 agreement by annexing Crimea in 2014 and invading Ukraine in 2022. Ukrainian leaders now feel that NATO membership or nuclear weapons are needed for security from Russia. However, Ukraine would face technical and political challenges in acquiring nuclear weapons. ICAN says that Russia’s threats to use nuclear weapons increase the risk of nuclear war. Having once renounced nuclear weapons, Ukraine condemns threats to use them. Russia had to repeatedly use the “nuclear political threat card” to ward off greater NATO intervention in favour of Ukraine.
Other Nations That Renounced Nuclear Weapons
In addition to Ukraine, several nations that became independent after the Soviet Union imploded, including Belarus and Kazakhstan, voluntarily relinquished their nuclear arsenals, choosing peace over military power. South Africa is the only country in the world to have developed and then dismantled its nuclear program. They all signed various international treaties like the Nuclear Non-Proliferation Treaty (NPT) and the Budapest Memorandum to ensure a safer world.
Countries Seeking Nuclear Weapons on Their Soil
After Russian threats to use nuclear weapons in Ukraine, Poland’s President Andrzej Duda has asked the US to share nuclear weapons with Poland. Poland has also shown interest in France’s offer to extend its nuclear umbrella to European allies. Poland is concerned that it could be Russia’s next target and wants nuclear deterrence.
With North Korea pushing ahead with nuclear weapons and its ballistic missile program, and threatening overtures, South Korea has expressed interest in a nuclear sharing arrangement with the US or in having US nuclear weapons stationed in South Korea. South Korea is concerned about being in the dark about the US nuclear policy and whether the USA will protect it from a nuclear threat.
Country-wise Nuclear Weapons Holdings
The countries with nuclear weapons are Russia, the United States, China, France, the United Kingdom, India, Pakistan, Israel, and North Korea. Russia has the most nuclear weapons, with over 5,500 warheads. The United States is a close second with 5,044 nuclear weapons, and some are hosted in other countries. China is closing in on 500 nuclear weapons. France (290), the UK (225), India (180), Pakistan (170), and North Korea have around 40-50 weapons. Israel has not officially declared itself as a nuclear weapons state and has estimated 90 warheads and material for up to 200.
The United States, Russia, and China are continuing to modernise their nuclear weapons and increase their numbers. The United States and other countries negotiated the NPT in 1968 and the Comprehensive Nuclear Test Ban Treaty (CTBT) in 1996. India, Israel, and Pakistan never signed the NPT. North Korea withdrew from the NPT in 2003, but its withdrawal is not recognized by France. Among the countries with suspected nuclear activities is Iran.
START Treaty
The Strategic Arms Reduction Treaties (START) were agreements between the United States and the Soviet Union (and later Russia) to reduce their strategic nuclear weapons arsenals. START I, signed in 1991, was meant to reduce and limit the number of nuclear weapons. It included provisions for on-site inspections and data exchange to verify compliance. It was considered one of the most successful arms control agreements, with 80 percent of the world’s strategic nuclear weapons dismantled by the time of its full implementation in 2001.
START II (1993) was to further reduce strategic offensive arms. Called for reducing strategic warheads to 3,800–4,250 by 2000 and to 3,000–3,500 by 2003. It was never entered into force due to a lack of ratification by the Russian Duma and the US Senate’s refusal to ratify an addendum to the treaty.
New START (2010) was to replace START I and the Strategic Offensive Reductions Treaty (SORT). It was to set limits on deployed strategic warheads (1,550), deployed and non-deployed ICBM launchers, SLBM launchers, and heavy bombers (800), and deployed ICBMs, SLBMs, and heavy bombers (700). It came into force on February 5, 2011. Later, the United States and Russia agreed to extend New START by five years, until February 5, 2026. On February 21, 2023, Russia announced it was suspending the implementation of New START.
Nuclear Umbrella
The “nuclear umbrella” is a guarantee by a nuclear weapons state to defend a non-nuclear allied state. The context is usually the security alliances of the United States with Australia, Japan, South Korea, the North Atlantic Treaty Organization (much of Europe, Turkey and Canada) and the Compact of Free Association (the Federated States of Micronesia, the Marshall Islands, and Palau). Those alliances were formed during the Cold War. For some countries, it was an alternative to acquiring nuclear weapons themselves; other alternatives include regional nuclear-weapon-free zones or nuclear sharing.
NATO assumed American nuclear power as a major component of the defence of Western Europe from a possible Soviet invasion. Most non-Communist European states joined the alliance, although some (Ireland, Switzerland, Austria, Sweden, Finland) maintained an official policy of neutrality. Sweden and Switzerland considered developing their nuclear weapons but abandoned the idea. Finland and Sweden have just joined NATO. Two other states have formally informed NATO of their membership aspirations: Bosnia and Herzegovina and Georgia. Kosovo also aspires to join. Joining the alliance is a debated topic in several other European countries outside the alliance, including Armenia, Austria, Cyprus, Ireland, Malta, Moldova, and Serbia.
After the end of the Cold War, the United States promised its the role of a “nuclear umbrella”. The US now has security alliances of this nature with around 30 countries, many within NATO itself. The US understood the power of deterrence with nuclear weapons early on, beginning with the concept of massive retaliation during the Eisenhower administration. In turn, the covered countries did not pursue nuclear weapons programs themselves.
Recent developments have caused concern. Currently, the United States holds only some “nonstrategic” military weapons in Europe, and these aid in reassuring countries under the umbrella, and emphasizing their role as a deterrent.
ANZUS is a security treaty between Australia, New Zealand, and the United States that was signed on September 1, 1951. This treaty was meant to assure peace in the South Pacific region. Later, New Zealand walked out of the treaty. In 1970, Australia considered embarking on nuclear weapons development but finally agreed to sign the NPT. Today, the Australian leaders publicly acknowledge the country’s reliance on the US nuclear umbrella.
Like Germany, Japan had a lab-based nuclear weapons program during World War II. After the atomic bombings of Hiroshima and Nagasaki and the deconstruction of the imperial military, Japan came under the US “nuclear umbrella” on the condition that it would not produce nuclear weapons. Japan and the United States also have a major missile defence accord to mitigate the North Korean nuclear threat, among others, and have deployed the Aegis Ballistic Missile Defence System jointly.
Following the Korean War, South Korea was welcomed under the US “nuclear umbrella” in 1953. The agreement also aligned with the US non-proliferation objectives by eliminating the need for South Korea to develop its own nuclear weapons program. The US initially positioned tactical nuclear weapons on the Korean Peninsula, but these weapons were retracted in September 1991.
Like NATO, the members of the Warsaw Pact were protected by nuclear weapons of the Soviet Union, with the weapons being deployed either in Soviet territory or closer to NATO in the territory of the other member states, particularly Poland. Unlike NATO, however, there was no nuclear sharing and all weapons remained completely under Soviet control. One member of the Warsaw Pact, Romania, did consider developing its arsenal but later abandoned it.
The 1994 Budapest Memorandum was meant to provide assistance to Ukraine, as a non-nuclear-weapon state party to the NPT, if Ukraine should become a victim of an act of aggression or an object of a threat of aggression in which nuclear weapons are used.
In a unilateral statement in 1994, China provided Ukraine with a nuclear security guarantee. When asked about the pact during a news conference on 3 March 2022, China’s Foreign Ministry spokesman sidestepped the question.
Ballistic Missile Defence
Missile defence provides an “umbrella” of another kind against nuclear attack. NATO had an expansive strategy concerning missile defence against nuclear, biological, or chemical (NBC) threats.
The Anti-Ballistic Missile (ABM) Treaty was an agreement between the United States and the Soviet Union to limit the development of their ABM systems. The treaty was signed in 1972 as part of the Strategic Arms Limitation Talks (SALT I). To maintain the balance of nuclear power between the two countries. The United States withdrew from the treaty in 2002.
In March 2013, the first European theatre missile interceptor system test proved successful in working in conjunction with NATO’s Interim Ballistic Missile Defence (BMD) command and control system. The United States’ contribution to the NATO BMD is through its European Phased Adaptive Approach (EPAA). Turkey hosts the United States’ BMD radar in Kürecik. Romania hosts a United States Aegis Ashore Site at Deveselu Military Base. Germany hosts the command centre at Ramstein Air Base. In addition to the EPAA, Spain holds four multi-mission BMD-capable Aegis Ships at the Rota Naval Base. All are voluntarily hosted. A Missile Defence Advocacy Alliance (MDAA) was formed as a public initiative.
To Summarise
US President Donald Trump’s recent foreign-policy moves to woo Russia have somewhat alienated the country’s European allies and shaken up Ukraine’s self-confidence. Trump’s approach is to stop the war that Ukraine cannot win and reduce the heightened risk of nuclear weapon use. What bothers, of course, is the threat and risk of fresh nuclear proliferation. Many countries will now be incentivized to build their arsenals. That would also mean increased risk of nuclear use, or even an accidental launch.
The 1993 denunciation of nuclear weapons by South Africa was a unique case. Threshold countries like South Korea, Japan, Iran, and Saudi Arabia could be the first to build nuclear weapons. Japan wants security from the Chinese threat. Some other technologically advanced countries like Germany, Belgium, Italy, Spain, and the Netherlands could be next.
The USA feels that it has spent too much on securing others, who themselves were busy building their economies and creating welfare states. One offshoot of the American nuclear umbrella was the phenomenal containment of nuclear proliferation. Today, 190 countries are parties to the NPT. To some extent, it was possible because of US assurances about their security.
Europe is now unsure that the United States would stand by them in the case of a nuclear threat from Russia. Some U.S. allies like Japan, Taiwan, and South Korea are threatened by China or North Korea. They, too, are asking the same question. All three have technology capabilities to go nuclear. Once it begins, there might be a domino effect leading to several more nuclear states.
There is also a wave of right-wing nationalism sweeping many countries, including Italy, France, Germany, the Netherlands and Poland. Some of them are talking of independent power structures and going nuclear. Berlin is more seriously reconsidering. Iran, too, will have a new incentive. The desire to have the bomb is increasing.
One school of thought is that the presence of nuclear weapons would reduce the risk of full-scale conventional war. They quote China-India border skirmishes, and even the Kargil war between nuclear India and Pakistan. The dangers of nuclear escalation would always lurk in the background. After China tested a nuclear weapon in 1964, it more willingly came out of the Soviet fold, causing a split.
The risk of terrorist action will increase if more nations acquire nuclear weapons. Already, there have been cases in Pakistan where terrorists have attacked a nuclear missile storage facility, a nuclear airbase, and one of the country’s main nuclear weapon assembly sites. There will also be a higher risk of nuclear accidents.
Till now, more than 88 percent of nuclear weapons are with the two superpowers. China already has plans to increase to 1,500 warheads. India will also be forced to increase numbers. The two have already acquired multi-warhead (MIRV) capability. Pakistan may follow suit. The risk of rapid build-up of arsenals is visible.
Conscious of the threat of nuclear weapons from adversaries in the immediate neighbourhood, Israeli jets had bombed a North Korea-designed nuclear reactor built in Syria, and the Osirak reactor in Iraq. They have been directly threatening Iranian nuclear facilities.
Despite progress in reducing nuclear weapon arsenals since the Cold War, the world’s combined inventory of nuclear warheads remains very high. Nine countries possessed roughly 12,331 warheads as of the beginning of 2025. Over 3,000 of these are retired, but still relatively intact and usable. Some 3,904 are deployed with operational forces (on missiles/submarines or at bomber bases). Of those, approximately 2,100 US, Russian, British and French warheads are on high alert, ready for use at short notice.
Instead of planning for nuclear disarmament, the nuclear-armed states appear to plan to retain large arsenals for the indefinite future. As such, they are in conflict with the objective and spirit of the NPT.
Nuclear weapons are here to stay. Technology is improving. Numbers are going up. Most treaties limiting deployments and numbers are currently defunct or held in cold storage. Global defence spending is going up considerably. With the unfolding US-Russia-Ukraine dynamics, there is a possibility of new possessors. These are troubling times. Keep fingers crossed and hope that the future is better than worst.
Air Marshal Anil Chopra (r) is an Indian Air Force veteran fighter test pilot and former Director-General of the Center for Air Power Studies in New Delhi. He has been decorated with gallantry and distinguished service medals while serving in the IAF for 40 years.
