In an example of Both Sides Have a Point, screenwriter Francis Ford Coppola said he wrote the script so that it would please both the anti-war left, who saw Patton as a warmonger and bully that slapped a shell shocked soldier, and right-wing 'hawks' who saw Patton as a great general and war hero.
Director Oliver Stone believes because President Nixon loved Patton and repeatedly watched it at the White House, it gave him the impetus to further escalate the Vietnam War by bombing Cambodia. The bombing of Cambodia led to the rise of the Khmer Rouge. Therefore, Stone says, the movie Patton is responsible for the genocide of millions in the Killing Fields!
Previously marked under Insane Troll Logic, but given its assumptions (the film made Nixon bomb Cambodia) the conclusion is actually logically valid. (Some historians would argue that "the bombing of Cambodia led to the Khmer Rouge" would also be an assumption, as the Khmer Rouge could well have won without the bombing boosting recruitment.)
As a matter of fact, George C. Scott seemed to believe this himself. When asked for permission to use a scene of the Nixon family watching Patton for a biopic on Nixon, Scott refused.
In a case of Hilarious in Hindsight, Francis Ford Coppola was fired as screenwriter from the film. The reason given? The opening scene. Yes, the same opening scene that has become an icon and been parodied countless times.