Behind Kim's Back
Austin Bay describes what might be called Trump's "Sam Spade" strategy for handling North Korea. The fictional Spade as you may recall from the Maltese Falcon faced the problem of neutralizing an armed gunman. He did this by ignoring the thug while convincing his boss that gunplay would be in neither of their interests.
Bay notes that Donald Trump's Twitzkrieg against Kim Jong Un takes a similar tack. Trump reminds China that a nuclear armed Pyongyang -- not Beijing -- would hold the key to war and peace in North Asia, an intolerable state of affairs for the control freaks in the Communist Politburo. He cites Bill Emmot's article as a summary of the argument that China would be safer if Kim were out of the loop. Emmot writes:
Fewer, however, have recognized that the least bad military option – the one implied by US President Donald Trump’s insistence that China take responsibility for its dangerous neighbor – is a Chinese invasion, or regime change forced through China’s threat to launch one. ...
So if China were to combine threats of invasion with a promise of security and nuclear protection, in exchange for cooperation and possible regime change, its chances of winning over large parts of the Korean People’s Army would be high. Whereas a nuclear exchange with the US would mean devastation, submission to China would promise survival, and presumably a degree of continued autonomy. For all except those closest to Kim, the choice would not be a difficult one. ...
Successful use of hard power would bring China, to borrow the distinction coined by Harvard’s Joseph S. Nye, huge reserves of soft power. ... This scenario may well never happen. But it is so logical that the possibility of it should be taken seriously. It is, after all, China’s best opportunity to achieve greater strategic parity with the US in the region, while removing a source of instability that threatens them both.
So why not take him out of the loop?
Trumps strategy is to push until something breaks betting that Chinese link with Pyongyang will give before Beijing's link with the rest of the world snaps. Ratcheting up the rhetoric with Kim is a big risk. But arguably the real gamble has already been taken by letting Kim get nukes in the first place. The failure of past administrations to contain nuclear proliferation has already rolled the dice. We are only living in the world they allowed to happen.
The weakness of Trump's strategy is it can't roll back the failure of nonproliferation -- it can't uninvent the gun in the gunman's hand -- it can only try to shift control from Wilmer to Kaspar Gutman or analogously the nuclear trigger from Pyongyang to China. It may never work until a sufficiently scary incident occurs to jolt Beijing into collecting the WMDs.