Javier C. Hernández, The New York Times (gift link):

At an otherwise congenial meeting with Japan’s prime minister, Sanae Takaichi, in the Oval Office on Thursday, Mr. Trump invoked the Japanese attack on Dec. 7, 1941, which led the United States into World War II. He was responding to a question from a reporter about why Japan and other allies had received no advance notice of the U.S.-Israeli assault on Iran.

“We didn’t tell anybody about it because we wanted surprise,” he said. “Who knows better about surprise than Japan, OK? Why didn’t you tell me about Pearl Harbor, OK? Right?”

There was some laughter from the officials and journalists gathered in the room. “You believe in surprise, I think, much more so than us,” he added.

As Mr. Trump spoke, Ms. Takaichi widened her eyes and appeared to take a deep breath. She kept her arms crossed in her lap and did not speak.

The remark was the latest example of Mr. Trump’s penchant for tossing aside diplomatic norms.

(You really must watch the video, and especially the reaction of the prime minister. It’s truly appalling.)

Two thoughts.

One: Donald Trump’s rapidly diminishing mental capacity—the effect of his ongoing descent into dementia, I presume—means he’s becoming less and less capable of hiding his instinctive nastiness. It would be funny if it wasn’t so embarrassing.

Two: In cracking his impudent “joke,” Trump unwittingly acknowledges that he believes his attack on Iran is as contemptible as Japan’s attack on Pearl Harbor. Sometimes, among the nastiness, the truth slips out.