Former President Donald J. Trump, who has been indicted by federal prosecutors for conspiracy to defraud the United States in connection with a plot to overturn the 2020 election, repeatedly claimed to supporters in Iowa on Saturday that it was President Biden who posed a severe threat to American democracy.

While Mr. Trump shattered democratic norms throughout his presidency and has faced voter concerns that he would do so again in a second term, the former president in his speech repeatedly accused Mr. Biden of corrupting politics and waging a repressive “all-out war” on America.

”Joe Biden is not the defender of American democracy,” he said. “Joe Biden is the destroyer of American democracy.”

Mr. Trump has made similar attacks on Mr. Biden a staple of his speeches in Iowa and elsewhere. He frequently accuses the president broadly of corruption and of weaponizing the Justice Department to influence the 2024 election.