A crowd of 10 million would exceed the entire population of Ahmedabad, estimated at eight million. Local officials estimate that it will be more like 100,000, making Mr. Trump off by only 99 percent. But Motera Stadium, which is not really fully built yet, is supposed to become the largest cricket arena in the world.

Other countries could not muster that show of force and so have taken advantage of whatever local assets they might have when Mr. Trump has come to visit. For Britain, of course, that would be Queen Elizabeth II, the world’s longest-reigning monarch, who welcomed him to Buckingham Palace last year with an 82-gun salute and a lavish white-tie state banquet.

“Crowd size is important to this president, so he was clearly thrilled to be told there would be seven million people on the streets” in India, said Peter Westmacott, a former British ambassador to the United States. “We couldn’t manage that in the U.K., but twice in the space of a year he seemed bowled over by the warmth of the welcome he received from the royal family.”

Mr. Trump was so blown away by the Bastille Day military parade in Paris when President Emmanuel Macron of France invited him in 2017 that the president insisted on organizing his own American equivalent along the streets of Washington as part of last year’s Independence Day celebration.

Perhaps with that in mind, President Vladimir V. Putin of Russia is trying to entice Mr. Trump to come to Moscow in May by inviting him to the Red Square parade marking the 75th anniversary of the victory over Nazi Germany. Mr. Trump, however, appears wary of the awkward politics of such a visit given the election year and Russia’s continued interference in American campaigns.

Japan eschews militarism and therefore military parades, but it sought to make Mr. Trump feel special by making him the first foreign head of state invited to meet Emperor Naruhito after his ascension to the throne. The Japanese also asked Mr. Trump to present his own trophy at a sumo champion match — a four-foot-tall object duly labeled the President’s Cup for the event.

“World leaders have learned to shorten or scrap the historical tours, remove local delicacies from the menu and focus on one thing only: feeding his ego,” said Julianne Smith, the director of the Asia program at the German Marshall Fund of the United States. “That’s taken different forms in recent years, but the goal is always the same — make Trump feel like he’s getting something unique: a parade in Paris, a grand state dinner at Buckingham Palace or a sumo match with a President’s Cup in Japan.”