Well, you are going to get splinters as long as those activists who oppose the war forget every lesson that they've learned from the past decade of protest. If they want to let the WWP/IAC folks lead the movement, then we're going to have to suffer through endless, boring events that have no militancy or direct action. If we're going to vote out democratic decision-making and let the anti-war group be run by a central committee, then we'll lose people who are treated like grunt workers. If we don't speak up about the sectarian opportunism that is being practiced by groups like the ISO, SWP, and IAC, then we'll end up helping them build their organizations, instead of building a network of groups, coalitions, and people who want to stop the war.
If local activists are losing steam and dropping out, it's because they've forgotten how the anti-globalization movements went about organizing its successful events. If you go back to the discredited methodology, then dont' be surprised if you lose steam and your protests suck.
Chuck0 Infoshop.org