I think John Winger put it well:
We're all very different people. We're not Watusi, we're not Spartans. We're Americans, with a capital A, huh? You know what that means? Do ya? That means that our forefathers were kicked out of every decent country in the world. We are the wretched refuse. We're underdogs, we're mutts! Here's proof: his nose is cold. But there's no animal that's more faithful, that's more loyal, more loveable than the mutt.