During the Cold War, the United States and the Soviet Union together amassed some sixty thousand weapons. Nuclear annihilation was a persistent threat, because each country possessed enough nuclear weapons to destroy the other several times over. Though the threat of a nuclear war is less immediate now than it was during the Cold War, it has not disappeared. As the number of countries that possess nuclear weapons grows, so does the potential for catastrophic conflict.
Nuclear conflict involving any of the five original nuclear powers—China, France, Russia, the United Kingdom, and the United States—is unlikely but remains a possibility. Although the number of weapons held by these countries has declined, most are reluctant to pursue complete disarmament because they see nuclear weapons as important components of their security posture. After all, nuclear weapons are the most powerful weapons ever created and few countries want to give them up.
In addition to these five countries, four other countries acquired nuclear weapons around the time of, or after the Nuclear Nonproliferation Treaty (NPT) went into effect.
Israel: believed to have nuclear weapons
Though Israel has never confirmed its status as a nuclear weapons state, it is believed to possess a considerable number of nuclear weapons. It never joined the NPT, the major treaty trying to halt the spread of nuclear weapons, but it has taken action to stop nearby countries from building a nuclear arsenal. Israel bombed suspected nuclear reactor sites in Iraq (1981) and Syria (2007).
It has also signaled that it would attack Iran if it feels threatened by the country’s nuclear program. A 2015 deal between Iran and China, France, Germany, Russia, the United Kingdom, the United States, and the European Union, limited Iran’s nuclear development and eased some international tension. However, in 2018, the United States alone withdrew from the agreement and reinstated sanctions against Iran, though the other parties involved have stuck to the agreement so far.
India and Pakistan: rival neighbors and nuclear powers
Sharing an 1,800-mile border, India and Pakistan have fought several conventional wars over one hundred thousand square miles of disputed territory. Both countries possess nuclear weapons. Neither joined the NPT, and both appear to be modernizing and adding to their stockpiles. Many policymakers and experts fear that nuclear war could break out between the two countries—or, even more concerning, that Pakistan could lose control of a nuclear weapon to terrorists.
North Korea: world’s biggest nuclear threat
Although North Korea is believed to have a small arsenal, its continued nuclear tests have raised widespread concerns over possible nuclear conflict. It withdrew from the NPT in 2003 and conducted its first nuclear test in 2006. Since then, it has threatened to use its nuclear weapons against the United States, Japan, and South Korea.