When Japan’s new Prime Minister Sanae Takaichi visited the U.S. President at the White House this week, the focus quickly shifted from bilateral relations and politics to something entirely different.

Last year, Sanae Takaichi became the first woman to hold the office. Takaichi is known for her conservative views, including her opposition to same-sex marriage, and is expected to take a sharp right turn on immigration and defense issues. She is a great admirer of former British Prime Minister Margaret Thatcher and has openly praised Trump.

However, during a joint press conference at the White House, the atmosphere became somewhat tense when Trump decided to make a joke. When a Japanese journalist asked why the United States had not warned its allies before attacking Iran on February 28, Trump referred to the Japanese attack on the U.S. in 1941.

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– Who knows more about surprises than Japan? Why didn’t you tell us about Pearl Harbor, said Trump.

Trump’s joke drew some laughter from journalists, while others found it less amusing.

According to Japanese journalist Mineko Tokito from the newspaper Yomiuri Shimbun, who was in the room at the time, the Prime Minister’s discomfort was “obvious.”

Nuclear Weapons

The attack on Pearl Harbor led to the U.S. entering World War II, and the conflict between the nations culminated in 1945 when the U.S. dropped two atomic bombs on Hiroshima and Nagasaki—the first and so far only use of nuclear weapons.

Hundreds of thousands of people were killed, with estimates ranging from 140,000 to 350,000 in Hiroshima and another 74,000 in Nagasaki. Japan surrendered unconditionally just a few days later. However, since 1952, the two nations have been allies.

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