But in more than two years in the Oval Office, the president has demonstrated an unmistakable pattern: He tends to believe what strongmen say.

“These aren’t leaders who are ‘frenemies,’” said Derek Chollet, the executive vice president of the German Marshall Fund and a State Department official under President Barack Obama. “These are folks where the presumption is that they are not on the level and we have to go into these conversations with deep skepticism and eyes wide open.”

Instead, Mr. Chollet said, Mr. Trump seems to accept the statements of foreign leaders at face value when it meshes with his own political interests.

In the case of Russia, Mr. Putin’s denials of election meddling fit with Mr. Trump’s claims that the investigations into whether his campaign conspired with Russia were nothing more than a hoax. After investing heavily in a diplomatic relationship with Saudi Arabia, it worked for Mr. Trump to accept the denials by Crown Prince Mohammed bin Salman of any role in Mr. Khashoggi’s killing.

The pattern continued in a 2017 call to Rodrigo Duterte, the authoritarian president of the Philippines who is accused of ordering extrajudicial killings of drug suspects, when Mr. Trump ignored those claims and instead told Mr. Duterte “what a great job you are doing.”

It is not hard to detect more than a bit of jealousy in Mr. Trump’s encounters with leaders like Mr. Duterte, Mr. Kim, Prince Mohammed and Mr. Putin. He seems to long for the efficiency of their style of government, under which they have sought to bend institutions and the law to their benefit.

Mr. Trump has lamented the “stupidity” of an American system that allows asylum seekers to have their day in court even as he has lauded the Chinese for being able to simply put drug dealers to death with minimal fuss. In China, he noted this month, a drug dealer gets “a thing called the death penalty.”