Why do so many people (particularly US employees) get so worked up about it?

When someone asks me which airline I'm flying, I don't think I've ever responded "American Airlines." Generally, my response is "American." I leave off the second word entirely. And no one has ever given me a hard time for omitting the second word.

Anyone know the URL for AA when the interwebs were invented (by that Tenn Senator)? That's right: www.americanair.com. Stayed that way for a couple years until AA obtained www.aa.com.

USAir, US Airways. What's the real difference? I just don't understand the all the indignity when someone refers to US as "USAir."