Even as America struggles to understand the Fort Hood massacre, right-wingers have embarked on a dangerous, dishonest campaign to blame the atrocity on "political correctness" - as if the very idea of tolerance and diversity in the U.S. armed forces is the crucial ingredient that allowed a madman to commit mass murder.

That's wrong. It's un-American. And extremist calls to subject Muslims to heightened scrutiny due solely to their religion are downright dangerous.

There's a lot we don't know about the massacre at Fort Hood; from the very start, even basic facts have been a moving target.

Early reports claimed the shooter, Maj. Nidal Hasan, had been killed (he wasn't).

The base officer said to have fired on Hasan was first identified as civilian Sgt. Kimberly...