They don’t need to jam into downtown DC, although that would make for great photos. If they split into 10 or 12 groups, they could blockade the bridges crossing the Potomac and Anacostia rivers and effectively turn DC into a ghost town, and equally impressive image. Federal employees from Virginia and Southern Maryland would be unable to get into their offices without enduring a several hour commute to the north and then back into DC.
That’s a solid plan.