“Just spoke to President Nayib Bukele of El Salvador,” President Trump tweeted Friday. “Will be helping them with Ventilators, which are desperately needed. They have worked well with us on immigration at the Southern Border.”

Mr. Trump’s call came the morning after the Salvadoran president triggered the shutdown of the country’s Legislative Assembly by tweeting that his government had “detected significant suspicion of Covid-19” in the chamber.

There was no scientific evidence of a coronavirus outbreak inside the congress. But lawmakers had voted to override a Bukele veto, and were debating the override of another veto the president was threatening, when he decided to break up the session.

It isn’t the first time Mr. Bukele has messed with the independence of El Salvador’s democratic institutions; he has repeatedly defied institutional checks on his power.

Mr. Bukele is popular and isn’t shy about his claims to independent action. His adversaries, he says, are corrupt and only he is honest enough to defend the interests of the Salvadoran people. The coronavirus is his latest excuse for absolute edicts.