When President Trump last attended a Group of 7 meeting in Canada, he was in many ways the odd man out.

At that meeting, in 2018, Mr. Trump called for the alliance of Western countries to embrace Russia, antagonized allies and ultimately stormed out of the summit over a trade battle he began by imposing metals tariffs on Canada.

As he returns on Sunday for the Group of 7 meeting in Alberta, those fissures have only deepened. Since retaking office, the president has sought to shrink America’s military role abroad and made threats to annex the summit’s host after embarking on a much more expansive trade war.

White House officials have said little about goals for the summit, but they are facing a self-imposed deadline of early July to reach trade deals. Mr. Trump’s trade adviser even promised in April that the tariffs would lead to “90 deals in 90 days.” Despite reaching framework agreements with Britain and China, the administration has shown scant progress on deals with other major trading partners.

The future of the president’s favored negotiating tool is uncertain as a legal battle over his tariffs plays out in the courts. But a failure to reach accords could lead the Trump administration to once again ratchet up tariffs and send markets roiling.

The summit also comes amid fears of a broader, regional war in the Middle East after Israel launched a surprise attack on Iran’s leadership and nuclear facilities last week, prompting both nations to trade strikes. World leaders will also be focused on surging oil prices and Russia’s war against Ukraine.