“The policies are converging,” said Stephen E. Biegun, deputy secretary of state in the Trump administration and a National Security Council official under President George W. Bush. “Continuity is the norm, even between presidents as different as Trump and Biden.”

Some former officials and analysts praised the consistency, arguing that the Trump administration, despite the deep flaws of the commander in chief, properly diagnosed important challenges to American interests and sought to deal with them.

Others are less sanguine. They say Mr. Biden’s choices have compounded problems with American foreign policy and sometimes deviated from the president’s stated principles. Senior Democratic lawmakers have criticized his meeting with Prince Mohammed and aid to the Saudi military, for instance, even though administration officials have promoted a United Nations-brokered cease-fire in Yemen.

“As time has gone on, Biden has not lived up to a lot of his campaign promises, and he has stuck with the status quo on the Middle East and on Asia,” said Emma Ashford, a senior fellow at the Atlantic Council.