North Korea's Nuclear Weapons Arsenal May Have Doubled in the Past Year

Kim Jong Un, North Korea, missile test
North Korean leader Kim Jong Un inspects the long-range strategic ballistic rocket Hwasong-12 (Mars-12) in this undated photo released by North Korea's Korean Central News Agency on May 15. KCNA via Reuters

North Korea could possess up to 20 nuclear warheads, double what it was thought to have just last year, according to an annual report released Monday from the Stockholm International Peace Research Institute (SIPRI).

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The country has conducted an unprecedented number of missile tests over the past year, as tensions with the United States have risen to boiling point. SIPRI estimates that the regime is expanding its arsenal with its increased nuclear focus and expenditures. It now believes that Kim Jong Un's regime has enough fissile material for up to 20 nuclear warheads, compared with the 10 it was thought to possess in 2016.

In May, North Korea conducted what was described by experts as its most successful missile test to date, with the country claiming that it could carry a large nuclear warhead and that it put the U.S. mainland within "sighting range." North Korea also has vowed to ignore warnings from the U.S. and the United Nations and conduct a sixth nuclear test.

But North Korea is far from the only country that has been improving its nuclear weapons capabilities. While the total number of nuclear weapons in the world has decreased slightly, from 15,395 to 14,935 in January 2017, all of the nine states possessing nuclear weapons have made significant investments in modernizing their arsenals.

The U.S. and Russia account for 93 percent of all nuclear weapons in the world, and, despite a bilateral treaty signed in 2010 to reduce nuclear weapons, the speed of that reduction has been slow, the SIPRI report notes.

Indeed, the U.S. is set to spend $1 trillion in the next 30 years modernizing its nuclear weapons arsenal.

"The projected increases in U.S. spending are not unexpected," SIPRI Associate Senior Fellow Hans Kristensen said. "The current U.S. administration is continuing the ambitious nuclear modernization plans set out by President Barack Obama."

Russia and China are engaging in their own modernization programs, while sparring neighbors Indian and Pakistan are growing their nuclear arsenals.

"Despite the recent progress in international talks on a treaty banning nuclear weapons, long-term modernization programs are under way in all nine states," said Shannon Kile, SIPRI senior researcher. "This suggests that none of these states will be prepared to give up their nuclear arsenals for the foreseeable future."

Of the 14,935 total nuclear weapons, 4,150 of them are classified as being deployed warheads, meaning they're already placed on missiles or located on bases with operational forces. The U.S. has 1,800 deployed nuclear warheads, compared with Russia's 1,950.