Peter Fonda has wanted to die at least since 1969, when a loose-triggered good ole boy decided he had to kill the witness too, and blow Fonda's character Wyatt away with a shotgun off his motorcycle in the final scene of Easy Rider. Wyatt's partner Billy had the wrong hair cut, you see, and the bad Yankee manners of the wrong hand gesture to go with it, while Wyatt had the wrong flag painted on the gas tank of his chopper and helmet. The Yankee fu was answered with the rebel yells of a twelve gauge.
Fonda repeated the performance in 1974's little-remarked Open Season as the character Ken, when the father played by William Holden hunts Ken down and kills him. Ken is a sick-in-the-head Vietnam vet who otherwise appears to lead a normal life but abducts and abuses, then releases and hunts and kills humans two weeks every year for sport with his buddies. As young men before the war they had raped Holden's daughter. She had had a child as a result, raised by the Holden character, and ended up in a mental institution. The Yankee fu was answered with the rebel yell of a vigilante's hunting rifle.
What Fonda couldn't bring himself to do with a gun in real life, he did to himself with drugs. For one reviewer of his 1998 Don't Tell Dad: A Memoir, too much of it "is a catalog of dope smoked". All along the real fu was to himself.