Donald Trump invites crisis at G7 by attacking allies, embracing Russia President Trump airs grievances in a 'poor, poor pitiful America' finale to G7 summit marked by tension, ultimatums and a suspiciously strong handshake.

Tom Nichols | Opinion columnist

Show Caption Hide Caption Trump departs G-7, en route to Singapore President Trump Departs G7, En Route Singapore

President Trump left the G7 summit in Canada early, declaring it concluded. It was actually still going on, but for him it was over, because he made a hash of it in record time.

Even before he got on Air Force One, Trump alienated our sister nation by embarking on a bizarre and inexplicable trade war. As he left he lashed out at our allies and partners in Europe — playing all of his greatest hits of imaginary American grievance, from “the United States has been taken advantage of for decades and decades” to “the European Union is brutal to the United States.”

Some of this could be excused as the normal wrangling among allies over trade and spending. This is not the first time that the U.S. and its partners have disagreed over important economic matters, and ironing out those disputes is why organizations like the G7 have summits in the first place.

But griping about the unfairness of international life wasn’t enough for the president, who knew he was going to face some angry questions about his impenetrably backward views on trade. So Trump upped the ante by raising the bafflingly dumb and politically ludicrous idea of bringing Russia back into the G7. Then he insulted Canadian Prime Minister Justin Trudeau on Twitter and said he wouldn't sign the final communique.

This is not a normal disagreement among allies; this is an American repudiation of what the G7 is supposed to represent.

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The president of the United States is now on record suggesting that a hostile power ousted because it occupied and annexed the territory of its neighbor be brought back into the good graces of the wealthy democracies. This, while Trump himself is trying to justify a trade war against our own allies on the grounds of national security.

A likely explanation, as always, is that Trump does not understand what the G7 is, or why it exists — or, for that matter, why Russia was kicked out of it. The G7 is meant to be a gathering of stable democracies with large economies. It was once the G8, when Russia was a fledgling democracy and the nations of the world were trying to assist the birth of a prosperous and democratic Russia.

But Vladimir Putin’s Kremlin, after mutating into a militaristic kleptocracy, has long since failed both requirements for the privilege of admission. The invasion of Ukraine and the annexation of Crimea finally smothered any hope of including Putin in the conclave of leaders representing peaceful democracies from Japan to the Mediterranean.

So what is the president doing? To judge from the way Trump’s comments caught his own foreign policy aides flat-footed, this is likely just another of the president’s thin-skinned reactions to criticism. The other G7 powers have made it clear to the United States that they will not shrink from the reckless trade wars Trump is trying to start with Europe and Asia.

Trump’s reaction to such opposition — at least when it comes from friends like Canada and France, rather than from the enemies he fears, like Russia and China — is to double down. Perhaps he raised the issue of inviting Putin merely because he knows it’s so ridiculous and insulting. Maybe he feels outnumbered at the G7 and wishes there was someone there who understands him.

The summit ended with a stern rejection from German Chancellor Angela Merkel and the other leaders that there would be no reconstitution of the G7 into a G8 with Russia anytime soon. This was probably gratifying to Trump, who does such things precisely to elicit such reactions from people who understand things better than he does. (Although one wonders if the president had second thoughts when French President Emmanuel Macron gripped his hand so tightly that it left a mark.)

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The Russians, in any case, must be mightily pleased. Dividing America from Europe has been one of Moscow’s core foreign policy goals since the early 20th century, and Putin — a man of the Soviet era masquerading as a modern Russian — will rightly consider himself one of the greatest masters of the Kremlin in Russian history if he helps to break apart NATO and neutralize the European Union.

Fortunately, the Russians have never succeeded in prying Europe away from the Americans. Now, however, the American president is doing it on his own, and accomplishing more damage in months than the Kremlin was able to do in years. This moment will pass, but a future U.S. president is going to have a lot of repair work to do – unless Trump’s penchant for attacking our allies and pleasing our enemies leads to a major economic or even military crisis sooner than we expect.

Tom Nichols, a professor of national security affairs at the Naval War College and an instructor at the Harvard Extension School, is the author of The Death of Expertise. The views expressed here are solely his own. Follow him on Twitter: @RadioFreeTom.