On Monday, about 60 anti-war protesters were arrested for blocking an intersection on Capitol Hill, blocking traffic for about 30 minutes. Another group of protesters were arrested for blocking the entrance to a Congressional office building. No one threw any bricks, no one got hurt, and it made the war at least a little inconvenient for a few people in Washington.
If commuters in more American cities had to deal with protests like this on a regular basis, I think you'd see more progress on the war -- if only because protests were making more people late for work.
So, really, which action had a more positive impact?
This one: http://www.flickr.com/photos/nowarnowarming ...or this one: http://www.youtube.com/watch?v=evAmWEw4dEM
Tactically speaking, there's a lot to be said for peaceful protests because they tend to give you the moral high ground -- the more brutal the pigs are, the better the protesters look. (Wasn't Nixon even said to be disturbed by the Kent State shootings?) Violence, property damage and sabotage should never be ruled out, but it seems to me that there should always be a strong presumption in favor of peace.
But maybe I'm just being a namby-pamby left-liberal, -N