In the letter, published by Vanity Fair
on Wednesday, the Oscar-winning screenwriter and creator of "The West Wing" expressed deep concern. "The world changed late last night in a way I couldn't protect us from," he wrote. "That's a terrible feeling for a father."
Sorkin wrote that Trump has "dangerous ideas, a serious psychiatric disorder, no knowledge of the world and no curiosity to learn."
Sorkin said it wasn't just Trump who won but the Ku Klux Klan, white nationalists, sexists, racists and buffoons.
"For the next four years, the President of the United States, the same office held by Washington and Jefferson, Lincoln and Teddy Roosevelt, F.D.R., J.F.K. and Barack Obama," Sorkin wrote, "will be held by a man-boy who'll spend his hours exacting Twitter vengeance against all who criticize him (and those numbers will be legion). We've embarrassed ourselves in front of our children and the world."
He wrote that NATO allies are afraid and economists are warning about a recession. (He also mistakenly said Dow futures dropped 7,000 points overnight after Trump was elected. Vanity Fair later corrected the figure to 700.)
Sorkin urged Hollywood and Democrats everywhere to fight, not move to Canada as some have suggested.
"We do what we can to fight injustice anywhere we see it -- whether it's writing a check or rolling up our sleeves," he continued. "We fight for a woman to keep her right to choose. We fight for the First Amendment and we fight mostly for equality -- not for a guarantee of equal outcomes but for equal opportunities. We stand up."