Instead, they denazified it

Hirohito remained emperor until his death and the imperial reign continues. Many war criminals were put into positions of power after the war. A couple examples include Yasuhiro Nakasone, the prime minister of Japan from 1982-87, who was directly involved in creating the "comfort women" system of sexual slavery during the war, and Nobusuke Kishi, the prime minister of Japan from 1957-1960. Here's a couple choice paragraphs from his Wikipedia page:

Known for his exploitative rule of the Japanese puppet state of Manchukuo in Northeast China in the 1930s, Kishi was nicknamed the "Monster of the Shōwa era" (昭和の妖怪; Shōwa no yōkai).[1] Kishi later served in the wartime cabinet of Prime Minister Hideki Tōjō as Minister of Commerce and Vice Minister of Munitions,[2] and co-signed the declaration of war against the United States on December 7, 1941.

After World War II, Kishi was imprisoned for three years as a suspected Class A war criminal. However, the U.S. government did not charge, try, or convict him, and eventually released him as they considered Kishi to be the best man to lead a post-war Japan in a pro-American direction. With U.S. support, he went on to consolidate the Japanese conservative camp against perceived threats from the Japan Socialist Party in the 1950s. Kishi was instrumental in the formation of the powerful Liberal Democratic Party (LDP) through a merger of smaller conservative parties in 1955, and thus is credited with being a key player in the initiation of the "1955 System", the extended period during which the LDP was the overwhelmingly dominant political party in Japan.

Japan continues to be a far-right haven to this day. Shinzo Abe, the recently assassinated former prime minister, was a direct descendant of Kishi and denied many of the crimes against humanity Japan committed during the war. He posed in a plane with the same numbers as the infamous Unit 731, a torture camp located in occupied China that was once under the control of his great-grandfather.

This only begins to scratch the surface of the far-right in Japan directly enabled by the United States. I hope you can see what a foolish statement you have made here.