Thanks to business interests around the world and his "citizen diplomacy," Hammer cultivated a wide network of friends and acquaintances. Late in life, he would brag that he had been the only man in history friendly with both Vladimir Lenin and Ronald Reagan.
Hammer remains a controversial figure because of his ties to the Soviet Union, which led to speculation that he was disloyal to the United States. During his lifetime, some also objected to him on the grounds that he had made an illegal campaign contribution to U.S. president Richard Nixon. Because of his tight control of Occidental Petroleum, Hammer is also sometimes blamed for the company's misdeeds, including environmental pollution, alleged mistreatment of workers, and four SEC investigations into financial improprieties.
Hammer hungered for publicity, and was the subject of major magazine and newspaper profiles from the 1920s through his death in 1990. He appeared frequently on television, commenting on international relations or agitating for research into a cure for cancer. As of 2008, he has been the subject of five biographies — in 1975 (Considine, authorized biography), 1985 (Bryson, Coffee table book), Weinberg 1989, Blumay 1992, and Epstein 1996 — and two autobiographies (1932 and a best seller in 1987). His art collection and his philanthropic projects were the subject of numerous publications as well.
Armand Hammer is buried in his family crypt at Westwood Memorial Park.