Protesters clash with police at Nato summit in Chicago It's crazy. There's so many people here," she said. Having Nato in town is kind of exciting. But she wondered whether the political agendas of the protesters were too unfocused to get diplomats' attention. "It seems like there's so many messages and people aren't really sure what they want to get accomplished," Westlake said. People just need to figure out what their argument is going to be. She worried that some protesters participated simply "to do stupid things" and cause trouble. Some participants called for the dissolution of Nato, the 63-year-old military alliance that is holding its 25th formal meeting in Chicago. It is the first time the summit has been held in a US city other than Washington. Diplomats at the meeting planned to discuss the war in Afghanistan, European missile defense and other international security matters. "Basically Nato is used to keep the poor poor and the rich rich," said John Schraufnagel, who traveled from Minneapolis to Chicago for the march. Since the end of the Cold War, he said, the alliance has become "the enforcement arm of the ruling 1 percent, of the capitalist 1 percent." The march lacked the size and single message that shaped the last major protest moment in Chicago, when nearly half a million people filled the city's downtown in 2006 to protest making it a felony to be an illegal immigrant. At one point, dozens of protesters in black clothing surged toward a much smaller group of police, throwing objects at them. The badly outnumbered officers fought back with truncheons, and people on both sides threw punches. As police reinforcements moved in, the pack of violent protesters fled. Authorities had planned to provide heightened security along the march route to protect people and property. But unseasonably warm temperatures raised concerns about the safety of the marchers themselves. The city provided water, rest stations and cooling buses along the 2ﾽ-mile protest route. The heat offered an unexpected benefit for police: making it easier to spot potential troublemakers. Before the summit, officers were told to keep an eye out for people wearing bulky clothing that could hide weapons or big pieces of cardboard that protesters could use to shield themselves against rubber bullets. But anyone wearing overcoats or sweatshirts was conspicuous on a 90-degree (32.22-Celsius) day, when many people wore T-shirts and shorts. Organisers of Sunday's rally had initially predicted tens of thousands of protesters this weekend. But that was when the G-8 summit of leading industrial nations was also scheduled to be in Chicago. Earlier this year, President Barack Obama moved the Group of Eight economic meeting to Camp David, the secluded retreat in rural Maryland. At the end of the march, police appeared to be using precisely the tactics Superintendent Garry McCarthy said they would - extracting individuals from the crowd and quickly getting them away from the rest of the demonstrators. Several times they could be seen pulling protesters into a line of officers, which parted briefly before quickly closing ranks again. Police also used "sound cannons" to give orders to demonstrators and tried to relieve officers who had become fatigued to help prevent any escalation in violence.