structural:expansion, stylistic:style_transfer, linguistic:voice_change, quality:correction
Controversy over political activities

Reviewing Franz Schulze's biography of Johnson, Kazys Varnelis wrote that "between 1932 and 1940, Johnson was an antisemite, fascist sympathizer, and active propagandist for the Nazi government." According to Varnelis, "Johnson makes no apologetic gesture toward his past behavior unless he is confronted by direct questioning, nothing even as paltry as an open letter accounting for and regretting his past actions and condemning the motives that led him to them". Johnson's activities included organizing political rallies for populist Huey Long; funding figures such as the right-wing agitator Joe McWilliams and his "Christian Mobilizers"; and writing for three periodicals, including Charles Coughlin 's Social Justice, whose "almost every issue contained articles about the 'Jewish conspiracy' or about destructive economic forces led by figures with Jewish names".

Because his family had a home in Germany and spent their summers there, Johnson traveled there frequently. As a Social Justice correspondent, he covered the huge Nazi rally at Nuremberg and the 1939 invasion of Poland with approval. The American correspondent William L. Shirer, traveling with him on the Nazi-sponsored press tour, labeled him in Berlin Diary, as "the American fascist" and suspected him of spying for the Germans. On the same tour, three weeks after Poland fell to the Nazis, Johnson, with Shirer, "was with German troops at the front as the guest of the Propaganda Ministry ". He wrote to a friend that "The German green uniforms made the place look gay and happy... There were not many Jews to be seen. We saw Warsaw burn and Modlin being bombed. It was a stirring spectacle."

In his Social Justice report on his trip to Poland, Johnson declared that the German victory amounted to an unmitigated triumph for the Polish people and that nothing in the war's outcome need concern Americans. Johnson went on to say that German forces had not significantly harmed Polish civilians, and said that "99 percent of the towns I visited since the war are not only intact but full of Polish peasants and Jewish shopkeepers." He said reports of Nazi mistreatment of Poles was "misinformed". Referring to political developments in France, Johnson wrote in Social Justice that "Lack of leadership and direction in the state has let the one group get control who always gain power in a nation's time of weakness—the Jews". In 1940 Johnson quit journalism and distanced himself from politics.

In April 1942, on reports that Johnson might be working in Colonel Donovan 's Office of the Coordinator of Information, the United States Assistant Attorney General James H. Rowe wrote to Director Hoover, saying, "I can think of no more dangerous man to have working in an agency which possesses so many military secrets." Johnson was later investigated by the FBI, but no charges were brought against him, and he was cleared for military service.

Johnson was inducted into the U.S. Army in Cambridge, Massachusetts, on March 12, 1943, but controversy continued. His name arose again in the so-called " Great Sedition Trial " of 1944 through his former contacts in the 1930s with its main target, the former diplomat and economist Lawrence Dennis, who in the 1930s supported fascist economics as an alternative to capitalism. Dennis was charged with sedition, or advocating the forcible overthrow of the U.S. government, under the Smith Act. Johnson was accused of "close and steady contact" with Dennis in the spring of 1938, and providing financial support towards publishing Dennis's 1940 book The Dynamics of War and Revolution. Johnson had already testified in 1942 in the government case against another former associate, the German poet and journalist George Sylvester Viereck in 1942. The ongoing federal case against Dennis, an FBI investigation, and a congressional investigation investigated about 30 people, including Johnson, but in the end he was not charged. Johnson was formally asked to appear at trial as a witness, and—by his own account—was speaking to prosecutor O. John Rogge, but after Judge Edward C. Eicher died of a heart attack a mistrial was declared and the case was dropped.

In 1993, when asked by Vanity Fair about his past political views, he said, "I have no excuse (for) such unbelievable stupidity.... I don't know how you expiate guilt."

In 1956, he donated a design for Congregation Kneses Tifereth Israel in Port Chester, New York. Architecture professor Anat Geva observed in a paper that "all critics agree that his design of the Port Chester Synagogue can be considered as his attempt to ask for forgiveness."

He discussed his trips to Germany and his infatuation with fascism in a 1996 interview with Charlie Rose. He said, "It was the stupidest thing I ever did, and I never forgive myself and I never can atone for it. There's nothing I can do... That's been torture to me ever since." He admitted to Rose that, while he had "difficulty" with Franklin D. Roosevelt because of his inability to achieve what he set out, he "worshiped the man" and "voted for him four times." Replying to Rose asking if he liked "strong figures", he said "Sure do. I like good architects that are strong, like Gehry."

In 2018, Nikil Saval wrote in The New Yorker that "Johnson would later describe Hitler as 'a spellbinder'; in 1964, well after he had been forced to abjure his Nazi past, he insisted in letters that Hitler was 'better than Roosevelt.'"

In 2020, in the wake of the murder of George Floyd and the wave of place name changes that followed, the Johnson Study Group—a group of 40 architects, designers, and educators—approached the Museum of Modern Art asking that honors given to Johnson be removed from public view, citing his "commitment to white supremacy", spread of Nazi publications, involvement with American fascist politics, and "effective segregation" of the architectural collection at the museum. "When it comes to racist urban planning policies in the 20th century and a deeply Eurocentric antiblack archive of American architecture," V. Mitch McEwen said, "MoMA under white supremacist Philip Johnson did largely create the problem. It innovated white supremacy in architecture... where under his leadership not a single work by any Black architect or designer was included."

In a 2020 article in Elle Decor magazine, articles editor Charles Curkin asked Pritzker Prize laureate Balkrishna Doshi if the architecture world was due for a reckoning, citing the Museum of Modern Art 's chief architecture and design curatorship still being named after Johnson. Doshi replied that "Life itself is due for a reckoning, and architects must give respect to life."

In 2020, Johnson's name was dropped from the Harvard University Philip Johnson Thesis House, which was designed by Johnson. Sarah Whiting, dean of the Harvard Graduate School of Design, announced the change on December 5, 2020, citing Johnson's "widely documented white supremacist views and activities."