The president is already making costly unforced errors ahead of his trip to Asia:

Taking a page from former U.S. leader Richard Nixon, current President Donald Trump has warned China that it must do more to rein in North Korea’s nuclear ambitions or face “a big problem” with “warrior nation” Japan.

“Japan is a warrior nation, and I tell China and I tell everyone else that listens, I mean, you’re gonna have yourself a big problem with Japan pretty soon if you allow this to continue with North Korea,” Trump said during an interview on the Fox News program “The Ingraham Angle” on Thursday, a day before departing on his first Asia tour as president.

Threatening China that they will have a “big problem” with Japan if they don’t become more cooperative on North Korea is about as tone-deaf and counterproductive as it gets. Anti-Japanese sentiment among Chinese nationalists has been extremely high in recent years, especially since the the Senkaku dispute heated up. Few things are less likely to make Beijing become more accommodating than something like this. The history of Japanese invasion and occupation of China makes referring to Japan as a “warrior nation” in this context deeply insulting in any case. If there was any chance of obtaining more Chinese cooperation on North Korea, summoning up old resentments and reopening old wounds among the region’s other countries with comments like these will quickly put an end to it. James Fallows comments:

4. China always on hair-trigger for new Japanese “aggression.” This is most destabilizing point a US leader could make.

— James Fallows (@JamesFallows) November 4, 2017

I doubt that the Japanese government wants to be volunteered for this “warrior” role. While Japan may amend its constitution in the future, post-WWII Japanese political culture has emphasized the rejection of the country’s militarist past. Trump’s remarks seem designed to alarm Beijing and embarrass Tokyo, and neither of these advances U.S. interests. As Fallows said, stoking tensions between Japan and China is a dangerous and destabilizing thing to do, but Trump has done this in typical off-the-cuff fashion with no understanding of the implications of what he said.