Striking the pose is as far as the VSG has thought our his standoff with Trudeau

I think Jim Geraghty at NRO has it about right:

Of course, when Trump articulates these complaints [about allies' tariffs], he rarely leaves a sense that these are moderate but resolvable problems in an otherwise healthy relationship. There’s a long tradition of countries cutting their allies slack that they wouldn’t cut to neutral countries or hostile states, but this

carries no weight in Trump’s mind. From his perspective, the other country’s misdeed defines the relationship, and anything else is window-dressing.

Trump and his fans believe he’s demonstrating “toughness” in ways that previous presidents couldn’t. Perhaps. The question is, what happens after you’ve demonstrated your toughness? Does the other side capitulate, or does the other side dig in? No doubt it’s cathartic to visibly rage at the other side, but does it get you where you want to go?

Trump now interacts with the prime minister of Canada the same way he lashes out at Rosie O’Donnell, Mika Brzezinski, or Attorney General Jeff Sessions, by ripping into him on Twitter: “PM Justin Trudeau of Canada acted so meek and mild during our @g7 meetings only to give a news conference after I left saying that, ‘US Tariffs were kind of insulting’ and he ‘will not be pushed around.’ Very dishonest & weak. Our Tariffs are in response to his of 270% on dairy!”

Trump’s trade adviser, Peter Navarro, raged on Fox News Sunday: “There’s a special place in hell for any foreign leader that engages in bad faith diplomacy with President Donald J. Trump and then tries to stab him in the back on the way out the door . . . that’s what bad faith Justin Trudeau did with that stunt press conference.”

Talk about turning it up to eleven. When U.S. policymakers tell a foreign leader that there’s a special place in hell waiting for him, it’s usually a brutal dictator who’s committed atrocities and human-rights abuses.

I guess the thinking is that U.S. tariffs will hurt Canadian workers worse than Canadian tariffs will hurt U.S. workers, and Trudeau will come back to the table, begging for relief. Of course, according to the Office of the U.S. Trade Representative — Trump’s own administration — in 2017, the U.S. exported about $8 billion more to Canada in 2017 than it imported. (The figures are a little muddied by goods that Canada exports to places such as Mexico by shipping them through the United States.)

When Trump and his team denounce Trudeau in such strong and personal terms, do you think they weaken or strengthen his resolve? Do you think they made it more likely or less likely that Trudeau will return to the negotiating table, ready to make concessions? 

What is it that the president and the administration really want? My suspicion is that for Trump, the tough stance is the end, not the means to the end. Getting others to perceive you as “tough” and not easily swindled is the actual desired outcome, not the particular policy concessions. If the concessions come, great. If it turns into a prolonged, standoff, that’s fine; that’s just another opportunity to demonstrate “toughness” in a test of wills.

Given the implausibility of other explanations, this sounds likely.