P. took the subway to Bowling Green. On his way to the exit, he passed a line of police officers accompanied by bomb-sniffing dogs. Outside, police had surrounded the “Charging Bull” with barricades and, a few blocks north, sealed off a stretch of Wall Street around the Stock Exchange. P. tried to look nonchalant as he carried a black messenger bag that contained a first-aid kit, a bottled solution of liquid antacid and water (to remedy the effects of tear gas and pepper spray), fifteen Clif bars (carrot cake), and several hundred photocopied maps, showing seven possible locations. “We decided that low-tech communication methods would be best,” P. told me. “If we’d used a mass text message, or Twitter, it would have been easy for the police to track down who was doing this…”