President Trump is scheduled to depart for Canada on Friday morning for the annual G-7 summit meeting, a gathering of leaders of the United States and six of its main allies. But the two-day meeting comes at a fraught moment, with the American president locked in a bitter trade dispute with the other leaders over Mr. Trump’s imposition of tariffs. Here are five things to watch:

The locale: La Malbaie

If any place could soothe the tempers of G-7 leaders, it is the weekend getaway village of La Malbaie, 90 miles northeast of Quebec City, near the languid waters of the St. Lawrence River. Even the police, flown in from as far as St. John’s, Newfoundland, are friendly, waving cars through their blockades past the imposing Fairmont Le Manoir Richelieu hotel, where the leaders will meet.

The village’s waterside square, where locals celebrate holidays together, has been transformed into a “free speech zone,” but on Thursday evening, the only sound produced there came from birds.

The battlefield: Twitter

Forget the formal and old-fashioned statements from summit meetings past. In the hours before the opening of the gathering, Mr. Trump and the other leaders waged a nasty Twitter fight over trade, ditching diplomacy for schoolyard taunts.

Given Mr. Trump’s regular use of social media to attack his rivals — and the apparent willingness of Emmanuel Macron, the French president, to meet Mr. Trump on the digital battlefield — the summit meeting itself could play out on Twitter as well. The key accounts to follow: @realDonaldTrump, @EmmanuelMacron, @JustinTrudeau and @theresa_may.