Some people are trying to convince us that Biff Tannen shouldn't have given his 1955 self the Gray's Sports Almanac.
Biff Tannen didn't do anything wrong. He was a capitalist. He founded and ran BiffCo Enterprises.
Marty and the Doc were liberal sons of bitches. Although I don't really hate them that much. Marty liked to shoot guns, and the Doc invented a time machine. (By the way--he didn't steal it from Nixon. The Doc's uses a flux capacitor and plutonium. Nixon's uses a crucifix and a burning Dutch flag.)
Barack Obama, on the other hand, doesn't use guns and doesn't work. His favorite video game isn't Wild Gunman--it's Socialist Pac-Man. And he wants to tax people for inventing time machines. If Obama were President a hundred years ago, Tesla would've been in jail for tax evasion.
Liberals wanted to put Henry Ford, Andrew Carnegie, Thomas Edison, George Westinghouse, Cyrus McCormick, Alexander Graham Bell, and the Wright Brothers in jail. And they wanted to execute Eli Whitney.
Their main concern is benefitting illegal immigrants and Muslim terrorists, promoting atheism, and encouraging people not to have children.