Non-Blacks: Get thee on the FRONT lines and TAKE some of these police stares, snatch-and-grabs, threats, and abuses. As the protest footage shows? You still won't get the worst of what the police have to offer and your presence MIGHT compel more moderation in law enforcement excesses, more donations (your people are STILL a majority and the wealthiest; bring some of your #PrivilegeDollars to these social justice settings; lawyering and bail aren't free), and a more unified American face to the media space. Stop playing.
While I undestand the underlying sentiment, keeping non-blacks out of die-ins and such is short-sighted and counter-productive. The fewer non-black faces there are, the easier it's going to be for people to say, as Rod frequently says "a black problem" instead of "an American problem." Not to mention you're giving the Glen Becks and GOP Black Chicks of the world proof of how this is a bunch of race baiting rabble rousers rebelling without a cause.