You wish.
The Left as a group has been dead-ass wrong on almost every major policy, program, position, proclamation or idea they have had in the past thirty years. Economics, foreign policy, culture, you name it. Ask a really dedicated Leftist what the last big accomplishment of the liberals in America was. See how many pipe up with "civil rights."
Aside from a few notable exceptions (Horowitz, Bruce, Stein, etc.), how many do you see standing up and saying, "Wow. Guess I was really full of shit, huh?"
Being a Leftist means never having to say you're sorry.