On Sunday, North Korea exploded their largest nuclear device so far, a device which the North Korean government described as a hydrogen bomb capable of being mounted on a missile. If that’s true, it represents a very significant advance in North Korea’s nuclear weapon program. Even if it’s not true, even if the image of a supposed weapon was a mock-up and the source of the explosion was a much larger device, the size of the explosion itself indicated a sobering increase over previous such tests.

Experts estimated that the blast was four to sixteen times more powerful than any the North had set off before, with far more destructive power than the bombs dropped on the Japanese cities of Hiroshima and Nagasaki during World War II.

Reactions from Trump have included taking shots at South Korea over Twitter, and making astonishing threats about trade policy.

 After Kim Jong Un's regime carried out its biggest nuclear test so far on Sunday, Trump fired off a series of tweets, including a warning that he's considering "stopping all trade with any country doing business with North Korea."

The extraordinary remark was clearly aimed at China, which accounts for roughly 90% of North Korea's international trade.

China is such an important trade partner for not just North Korea, but the US, that Trump’s tweet represents a threat to commit economic suicide.

"This isn't even in the realm of the remotely plausible," said Edward Alden, a senior fellow at the Council on Foreign Relations who specializes in trade. "Even assuming trade with these countries could be cut off it would cause enormous damage to the U.S. economy."

And it's not clear this would have any effect on North Korea.

Trade between the U.S. and China was worth nearly $650 billion in 2016. China is the U.S.'s largest trading partner in goods, supplying products such as iPhones and toys as well as machinery and parts vital for American industry. It also buys a lot of U.S. farm produce like soybeans and high value exports such as Boeing (BA) passenger jets.

Placing any sudden restriction on trade between the US and China would result in a global economic disruption.

Meanwhile, in a speech at the  UN, Ambassador Nikki Haley has made some dire statements.

North Korea’s leader, Kim Jong-un, “is begging for war,” Nikki R. Haley, the United States ambassador to the United Nations, told the Security Council on Monday

However, unlike Trump who has repeatedly dismissed the value of diplomacy, Haley holds open hope that something other than war lies ahead.

Ms. Haley did not threaten unilateral military action by Washington or repeat President Trump’s statement on Twitter that South Korea’s call for more diplomacy was a form of “appeasement.” She said instead that “the time has come for us to exhaust all of our diplomatic means before it’s too late.”