I searched and didn't find this mentioned on kos anywhere and thought it deserved a look and some discussion. It's an article from yesterday's New Republic by Peter Beinart called
A Fighting Faith. Basically he's arguing that there's a similarity in the left of today and the left just after the second world war.
In the early part of the 20th century, the left had generally made common cause with the communists in fighting for worker's rights, women's rights, that kind of thing. In the late 1940s, however, it became clear that the USSR was a totalitarian nightmare, and not a beacon of hope.
A small group in the Democratic party decided it was thus unacceptable to continue to be simply non-communist, but that since communism had shown itself to be a threat to the liberal freedoms they enjoyed, they must be actively anti-communist. The article is quite long, so I won't try to summarize it all here, but he makes some interesting comparisons.
Just to give you an idea, he compares Michael Moore to the faction of the Democratic party that became known as the softs in the 1940s and considered the right much more dangerous than foreign totalitarianism. Beinart argues that American liberalism must again become a "fighting faith", and recognize that radical Islam is a greater threat to our values than the American right. I don't know how much of his argument I agree with, but it's really an excellent piece.