5 Questions About North Korea's Missile Test You Were Afraid to Ask

North Korea worsened global tensions and further solidified its threats against the U.S. this week when it tested its first intercontinental ballistic missile (ICBM).

After launching the missile, which is capable of reaching American territory, North Korea's leader Kim Jong Un said his nation’s nuclear weapons program will never be up for negotiations. He also warned that North Korea would "demonstrate its mettle to the U.S."

If you haven't been following the crisis closely, you might have some basic questions about it you're afraid to ask. Here are some answers:

Why do the U.S. and North Korea not get along?

The U.S. and North Korea's poor relationship stems back to the mid-20th century. After the Second World War, the U.S. took control of what became South Korea, while the Soviet Union oversaw the communist North. The two were temporarily established as separate countries in 1948, but in 1950 Pyongyang, backed by China, invaded the south in an attempt to reunify the peninsula, kicking off the Korean War. The U.S. led a U.N. effort to support South Korea in the bloody battle, which ended three years later. The war devastated the North, which, despite having around half of the South's population, suffered the vast majority of the conflict's casualties.

After the war, North Korea became a hermit state under Supreme Leader Kim Il Sung. Over the years, its totalitarian leaders — Kim Il Sung’s son Kim Jong Il, and subsequently his grandson Kim Jong Un — have repeatedly blamed the U.S. for its problems, particularly its economic sanctions and isolation. In return, America is wary of North Korea developing nuclear and ballistic weapons and launching an attack on U.S. soil, as it has threatened to do a number of times.

What is North Korea capable of doing?

U.S. officials have confirmed that North Korea did indeed launch an intercontinental ballistic missile (ICBM) on Tuesday, having initially said that the missile was only of intermediate threat. ICBMs are capable of carrying nuclear warheads distances of 5,600 km through the air.

That puts it within range of the United States. Although the missile only flew 933 km in this week's test, it reached an altitude of 2,802 km. David Wright, co-director of the UCS Global Security System, said that means the missile has the potential to travel 6,700 km. "That range would not be enough to reach the lower 48 states or the large islands of Hawaii," he wrote. “ But would allow it to reach all of Alaska.”

After the test, arms control specialist Jeffrey Lewis tweeted: “That’s it. It’s an ICBM. An ICBM that can hit Anchorage [Alaska] not San Francisco, but still.”

However, officials and analysts doubt whether North Korea has the capability to fit a warhead to that missile and bring it back into the atmosphere. Pentagon spokesman Peter Cook said last year: “The United States has not seen North Korea demonstrate a capability to miniaturize a warhead. We still feel confident that we can deter and respond to a missile threat from North Korea.”

The hermit kingdom is equipped with missiles that can travel shorter distances. In September 2016 it fired three missiles that each flew about 1,000 km before landing in the sea. In February 2017 it fired an intermediate-range missile that flew about 500 km, before falling again into the sea. These tests prove that North Korea can easily strike at its neighbors.

What has the U.S. done to stop North Korea?

The U.S. has periodically pursued diplomatic solutions to North Korea's isolation, but to no avail. Previous administrations have tried “freezes” of North Korea's nuclear-weapons programs in exchange for diplomatic inducements, although any successes were only temporary — such as a 2007 agreement by North Korea to shutter nuclear facilities that collapsed within two years.

In addition, the U.S. has heavily sanctioned North Korea's economy since 2008, when then-President George W. Bush issued an executive order labeling North Korea a national threat. In February 2016, President Obama tightened sanctions on the rogue state, a month after North Korea conducted a fourth test of a nuclear weapon.

President Donald Trump has signaled a more aggressive approach than his immediate predecessor, confronting Pyongyang and urging China to pressure North Korea to halt its nuclear ambitions. Earlier this year, Vice President Mike Pence warned that the “era of strategic patience” with North Korea was over. But the U.S. approach has in fact changed little since the Obama administration.

On Tuesday, U.S. and South Korean forces fired "deep strike" precision missiles into South Korean territorial waters as a response to North Korea’s latest actions. The U.S. and South Korea have staged annual joint military exercises in the region for decades; over 23,000 U.S. troops are stationed in the country.

Why doesn't the U.S. just bomb North Korea’s nuclear facilities?

Because it doesn't want to start a war. Any pre-emptive strike by the U.S. would have deadly consequences for its allies that neighbor North Korea. South Korea and Japan are well within North Korea’s striking distance; indeed, the city of Seoul is just 35 miles from the de-militarized zone between the two countries. There is no way to know for sure that any attack would completely destroy Kim’s collection of weapons, some of which are hidden in hillside bunkers.

“Military action just isn’t feasible — that’s the bottom line,” John Delury, an East Asia expert at South Korea's Yonsei University, previously told TIME. “It just doesn’t pass any cost-benefit analysis.”

Why does President Trump want China to resolve the North Korea issue?

Trump has put pressure on China to confront its neighbor and ally over recent missile launches that violated U.N. resolutions, believing only the Asian nation — with its vast economic leverage over North Korea — has the power to tame Kim Jong Un's aggressive behavior.

China has reduced exports of coal to North Korea in response to missile tests, but as Trump pointed out in a tweet on Wednesday morning, trade between the two has continued to surge. In the first three months of 2017, China-North Korea trade rose by 37.4% over the same period the year before.

In April, the U.S. President tweeted that "if [China] want to solve the North Korean problem, they will," but he later backtracked after a meeting with China's President Xi Jinping. "[I] realized it's not so easy," Trump told the Wall Street Journal following the meeting. "I felt pretty strongly that they had a tremendous power [over North Korea]... But it’s not what you would think.”

Trump said in the same WSJ interview that he offered Xi better trade terms with the U.S. in exchange for China's cooperation in taming North Korea. "I explained to the President of China that a trade deal with the U.S. will be far better for them if they solve the North Korean problem," he explained on Twitter. President Xi did not offer Trump any public commitments on North Korea in return.

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