Lennox Tierney was there, on the fifth floor of the Dai-Ichi Insurance Building in Tokyo, where MacArthur held court from 1945 to 1949, on the day Hirohito arrived. Now 93 years old, Tierney fears a brutishness he saw in MacArthur that day is being repeated by Americans involved in today's wars.
But these days, he says, the country can ill-afford such behavior.
In the years that followed the war, MacArthur came to be thought of as an expert in Japanese culture, but that's not what Tierney says he saw in the eminent general.
"He was culturally stupid," says Tierney, Japan's commissioner for arts and monuments during the occupation, now a semiretired professor and museum curator living in Holladay.
"Apology is a very important thing in Japan," said Tierney. "With us, we don't apologize unless we get caught with our hand in the cookie jar, but for the Japanese, there is a very strong sense of what an apology means."
But when the emperor arrived at his office, MacArthur refused to admit him or acknowledge him, Tierney said.
"MacArthur kicked off his shoes and just sat there, smoking his corn cob pipe with his feet up on his desk and didn't say a word," recalled Tierney. "He didn't even invite the emperor into his office."
"It was the rudest, crudest, most uncalled for thing I have ever witnessed in my life."
Tierney considers it fortunate that the general's imperial affront was never made public, as Japan's citizens likely would have been outraged.
He fears the mistakes of World War II are being repeated in Iraq and Afghanistan.
"Americans didn't know much about Japan prior to the bombing of Pearl Harbor," he said. "To most people, it was geisha girls and Mt. Fuji and that was about it. And that is where we got caught so terribly short, because here we were, at war with a major power that we didn't know much about. Here we were at war, and we couldn't even speak the language. We didn't know a thing about them."
Tierney himself didn't know much about Japan when, as a student at the University of California at Los Angeles, he was called on to study the nation's language, culture and history for the U.S. Navy.
"It was a funny choice," he said, "because I'd spent most of my life devoted to studying China."
But for the U.S. military that appeared to be close enough.
"That was a shame," he said. "We should have made a greater effort to understand them."
Now, he said, "we're doing similar things with our presence in the Middle East. We've caused such great harm by being culturally inept - and it may be even worse, because I think we know even less of Middle Eastern and Arabic languages and cultures."
In Japan, MacArthur's actions against the emperor were known only to a few people, who kept the insult a historical secret for decades, Tierney said. In today's world, where information travels so much faster than it did in the 1940s, such cultural affronts are not so easily concealed.
Though he doesn't consider himself an expert on the Islamic world, Tierney said he doesn't believe the cultural ideas of accepting defeat - prevalent among the Japanese - are present in the nations that the U.S. occupies today.
"So all of that, together, is a kind of cultural dynamite," he said.
Now, 65 years after the bombing of Pearl Harbor, Tierney says he is pleased that relations between the United States and Japan healed so well and so quickly. In the first years after the occupation, Tierney received degrees at two Japanese universities and he still travels frequently to the westernized Asian nation.
But he cringes at the suggestion, prevalent among members of the Bush administration, that Iraq will one day be an economic, political and cultural ally to the United States, similar to Japan.
"Today we have so much worse a situation," he said. "We have occupied a nation that never attacked us. Maybe we didn't like their government, but they never attacked us. And that is a bad problem, because we will never be able to claim the legitimacy we had in Japan."
And when the U.S. stumbles culturally, he said, there will be no one to keep the secret.