Democrats have also embraced the gritty, lo-fi aesthetic of internet memes. Mike Gravel, the former Alaska senator who is among the Democratic candidates for president, turned over his social media accounts to teenage supporters, whose pro-Gravel memes have made him a cult favorite online. Andrew Yang, the businessman who is running for the Democratic nomination on a platform of universal basic income, has tapped his online supporters, known as the “Yang Gang,” for catchphrases and campaign ideas. Other Democratic candidates have been experimenting with Instagram-ready moments — Elizabeth Warren’s kitchen beers, Beto O’Rourke’s dental appointment — with varying success.

Mr. Trump’s use of internet imagery is cruder than most. Last month, reporters began noticing that his re-election campaign had been using stock photo images in its targeted social media ads, including an ad featuring images of a “small American business” that turned out to be a storefront in Tokyo.

Fidelity to the facts, of course, has never been a hallmark of meme culture. A bigger worry for Mr. Trump, as his re-election campaign heats up, is that some of the largest repositories of pro-Trump internet content are drying up. Reddit’s largest pro-Trump forum, known as r/the_donald, was quarantined by moderators last month after users were found to be making threats against police officers and public officials. 8chan, a message board known as a hotbed of alt-right vitriol, was served with an F.B.I. search warrant in April, in response to evidence that the suspect in the Poway, Calif., synagogue shooting had been inspired by posts he saw there. And a number of Trump-supporting internet figures were barred by Facebook and Instagram this year for violating its policy against “dangerous individuals and organizations.”

These moves seem to have re-energized pro-Trump internet influencers in recent months, by uniting them around a shared concern over censorship.

It is ironic, of course, to complain about being persecuted from the cushy perch of a White House summit. And it reflects the shifting attitudes toward power that many pro-Trump internet influencers have had to adopt since Mr. Trump’s election, as they have gone from being anti-establishment mischief-makers to a state-sanctioned cheering section.

Whatever else it does, the White House’s social media function may serve the valuable purpose of shifting attention from the halls of Washington, where Mr. Trump holds ultimate power, to the platforms of Silicon Valley, where he doesn’t. The internet, after all, still loves an underdog.