When Prime Minister Giorgia Meloni of Italy convenes the leaders of the Group of 7 countries on Thursday at a luxury resort hotel overlooking the Adriatic Sea, she might be forgiven for thinking her guests are seeking a refuge.

Except for Ms. Meloni herself, every one of the leaders is arriving at the meeting beleaguered, embattled or endangered — an ill-starred convergence that speaks to the political tremors rattling across the West. It also doesn’t bode well for the results of a gathering that already faced vexing challenges, ranging from Russia’s war in Ukraine to China’s global economic competition.

Britain’s prime minister, Rishi Sunak, is three weeks away from an election in which his Conservative Party is expected to be swept out of power. President Emmanuel Macron of France has called a snap parliamentary election after his party suffered heavy losses to the far right in European elections.

Chancellor Olaf Scholz of Germany and his Social Democratic Party were humbled in those elections as well, while President Biden is in a dogfight with his predecessor, former President Donald J. Trump. Even Prime Minister Fumio Kishida of Japan faces rising unrest within his Liberal Democratic Party and may lose his job this autumn.

Prime Minister Justin Trudeau of Canada, who faces his own disenchanted public after more than eight years in office, spoke for his fellow leaders when he lamented the surge of populism in Europe and the United States.

“We have seen around the world a rise of populist right-wing forces in just about every democracy,” Mr. Trudeau said on Monday. “It is of concern to see political parties choosing to instrumentalize anger, fear, division, anxiety.”