Which Countries Have Nuclear Weapons?

There are nine countries in the world known to have arsenals of nuclear weapons: Russia, the U.S., France, China, the U.K., Pakistan, India, Israel, and North Korea.

That group of nine may soon become eight after North Korean leader Kim Jong Un reaffirmed in an agreement with President Donald Trump a longstanding commitment to "complete denuclearization" at a historic summit between the pair.

Kim promised to freeze Pyongyang's nuclear weapons testing program, which led it close to developing an intercontinental ballistic missile capable of delivering a nuclear warhead to the U.S. mainland. In return, America will halt its war games with ally South Korea.

The chart below, via Statista, shows the estimates of just how many nuclear weapons each of the nine states has, using data from the Federation of American Scientists.

Russia leads the world with 6,800 warheads. The U.S. is in second place with 6,600. Third, with significantly fewer, is France at 300. Next is China with 270 warheads, then the U.K. with 215, Pakistan has 140, India 130, Israel 80, and North Korea 20.

After the end of the Second World War, when America became the first and only state to use a nuclear weapon in combat—the two hydrogen bombs dropped on Japan at Hiroshima and Nagasaki—the Soviet Union acquired the same capability through its own research.

The subsequent Cold War triggered a nuclear arms race between the world's two superpowers under the doctrine of Mutual Assured Destruction, or MAD. This is a theory of deterrence that relies on each side having a nuclear arsenal of apocalyptic scale, creating a stalemate because neither could realistically win a nuclear war. Nuclear weapons proliferated as others conducted their own research before any international law was established to prevent or deter it.

In 1968, six years after the Cuban Missile Crisis almost sparked a nuclear war between the U.S. and Soviet Union, the Treaty on the Non-Proliferation of Nuclear Weapons was agreed.

Two years later, it was ratified. The treaty obliged signatories—among them the U.S., Soviet Union, the U.K., France, China and others—not to spread nuclear weapons by sharing them or the scientific knowhow behind their development and for those with arsenals to disarm.

There are now 190 signatories of the treaty. North Korea is now a non-party to the treaty after it withdrew in 2003 to pursue its nuclear weapons program. It had originally signed the treaty in 1985. Other non-parties to the treaty are those in the above list who also have nuclear weapons: India, Israel, and Pakistan. Israel does not declare itself to be a nuclear power, adopting a policy of ambiguity.

According to a paper called "Global nuclear weapons inventories, 1945–2010," published in the journal Bulletin of the Atomic Scientists, the U.S. stockpile of nuclear warheads peaked in 1967 at 31,255, before declining. The Soviet Union's stockpile peaked at 45,000 in 1986 before falling sharply as the Cold War ended and Russia pursued disarmament.

Iran is accused of harboring ambitions to develop a nuclear arsenal, despite being a signatory to the Non-Proliferation Treaty, and has conducted research to that end, though it claims only to have civil energy in mind.

But it entered into a deal, signed in 2015, to abandon nuclear weapons research and allow inspectors to verify its disarmament, in return for the lifting of economic sanctions.

That deal—formally titled the Joint Comprehensive Plan of Action—is now in jeopardy after President Trump pulled America out.