#Choe Sang-Hun - North Koreas Arsenal Has Grown Rapidly. Heres Whats in It.

SEOUL, South Korea - North Korea launched what it called a newly developed tactical guided missile on Thursday, violating international sanctions.

It was the country's first ballistic missile test in a year and its first provocation of the Biden administration, prompting President Joe Biden to warn that there will be "answers" if North Korea continues to escalate tensions on the Korean peninsula.

A senior North Korean official, Ri Pyong Chol, responded defiantly on Saturday, warning that if the United States continues to make "thoughtless comments without thinking about the consequences, it may face something that is not good."

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The United States has attempted both sanctions and dialogue to persuade North Korea to abandon its nuclear weapons programs.

None have worked.

Instead, North Korea has rapidly expanded its nuclear program and modernized its missile fleet under Kim Jong Un, the country's young leader. The expansion of the arsenal is a growing threat to the United States and its allies in the region. This is what it contains.

There are nuclear warheads and more.

North Korea's ballistic missiles can carry nuclear warheads, and the country conducted six increasingly sophisticated underground nuclear tests between 2006 and 2017. The last four of them occurred under Kim's direction.

Its last and most powerful nuclear test was carried out in September 2017, when North Korea claimed to have detonated a thermonuclear or hydrogen bomb. Estimates of the explosive power of the device ranged from 50 to 300 kilotons.

At just 100 kilotons, the test would be six times more powerful than the bomb dropped on Hiroshima in 1945.

North Korea has mined plutonium, an atomic bomb fuel, from its Soviet-designed nuclear reactor in Yongbyon, north of Pyongyang. It also uses centrifuges to produce weapons-grade enriched uranium, another bomb fuel. 

As of January 2020, North Korea had between 30 and 40 nuclear warheads and could produce enough fissile material for six to seven bombs a year, according to an estimate by the Arms Control Association.

Although the world is concerned about the North's nuclear weapons, the country has also stockpiled thousands of tons of chemical and biological weapons agents that it can launch with its missiles. When Kim's estranged half-brother, Kim Jong Nam, was killed in Kuala Lumpur in 2017, North Korea used the internationally banned VX nerve agent in the operation.

Its missiles can fly longer distances.

In 2017, North Korea made great strides in its weapons capabilities.

That year, the country fired its intermediate-range ballistic missile, Hwasong-12, over Japan and threatened an "enveloping" attack around the US territory of Guam. It also tested the Hwasong-14 and Hwasong-15, the country's first ICBMs.

At the end of the year, Kim claimed that his country had the ability to launch a nuclear attack against the continental United States.

After 2017, Kim stopped testing nuclear weapons and long-range missiles, but threatened to end the moratorium on him when talks with President Donald Trump collapsed in 2019.

During a nightly military parade last October, North Korea displayed a new unproven ICBM that appeared larger than any of the previous ones.

And at a party congress in January, Kim redoubled his accumulation of nuclear weapons, offering a long list of weapons that he said he planned to develop. They included "multi-warhead" nuclear missiles, "hypersonic" missiles, solid-fuel submarine-launched ICBMs and "ultra-modern tactical nuclear weapons."