Cops are held to a higher standard. It goes with the territory, I'm willing to cede that Gates was probably shouting. But unless he struck the officer (or threatened to do so) the exact moment he showed proof of residence the situation should have stopped. Immediately. Cop was wrong.
Having been in the situation myself all it takes is responding to an alarm at your bussiness. I had a gun pulled on me for playing Playstation. If you follow my posts on any sort of regularity you know I have no great love for African Americans, but every so often I'm reminded that I am infact African American, not American. The difference as it pointed out in this story is obvious.
Also no I wouldn't have a problem with a white man yelling and carrying on. Once you prove it's your house unless you are physically threatening the office he needs to shut his goddamn mouth and get to fucking stepping.