Brinkmanship

To many people, Trump's comment that he would reign "fire and fury" on North Korea seemed a counterproductive escalation of tensions. It appeared remarkably intemperate, particularly since the US had just scored what must be seen as an important and unexpected victory with unanimous support for tighter sanction by the UN Security Council.

That Russia and China voted in the affirmative is surprising and has received remarkably little media attention. That these two US adversaries - or at least non-allies - voted with the US suggests the situation has changed, either (or both) on the ground, or in their calculation of likely US actions. Compounding this was a remarkable statement from Beijing that it would not interceded on North Korea's behalf if DPRK were the aggressor.

First, it's worth considering how things might unfold. It is possible that the US might launch a preemptive strike against the DPRK. However, this is unlikely to gain any international support and could probably result in DPRK either launching an attack on the South or possibly on the US (though that would be suicidal and therefore highly unlikely). An attack on the South by the DPRK would be carnage for the population of Seoul. But a US first strike seems a low probably event.  But if the US were the aggressor, it would have to consider China's possible response so US military reaction might be muted.

Alternatively, the DPRK might strike first, either by firing missiles at the US base on Guam or firing them somewhere nearby but off-shore. The US response could be either defensive -- using the THAD system to destroy the Korean strike -- or offensive with an attack on DPRK military installations or even on Pyong Yang itself.  In either case, China has now said it will not come to the DPRK's aid so Kim must understand that there is little to restrain Trump from either military response. This must change Kim's calculus; without China's support, Kim could not escalate to an attack on the South or the US since either would provoke a strong response from the US and probably its allies in the region, which would spell the end for his regime.    

So back to Trump's intemperate comment. The uncharitable interpretation is that it was the ill considered bluster of a school-yard bully who is accustomed to getting his way by issuing threats. A second is that Trumps wants to provoke Kim into a first strike, giving him the cover and rationale for taking action to crush the Kim'd regime militarily. ( Of course the two interpretations are not mutually exclusive ). So the question remains, crazy like a fox or just plain crazy.