Why do people think the ACLU is leftist or anti-American?

Some people anyway. First off, the ACLU has fought on behalf of people/groups across the political spectrum including nazis and the Klan; about as right as you can get. They've also defended people who opposed those types.Second, they have no actual powers, all they can do is file lawsuits the same as you or I can. They can't force anyone to do anything, only a judge's order can. It seems like the people most annoyed by the ACLU are those who are breaking laws and have gotten used to getting away with it because no one brought it up. Again, all the ACLU can do is ask a judge to decide an issue, if they're wrong they'll lose. They stand up for everyone's rights that way. I can't think of anything more American.