Some veteran anti-war activists were concerned that any street violence — threatened by so-called "anarchists" — would hurt Obama and the Democrats when they need to be perceived as the party of change. Chicago's Democratic convention in 1968 is best remembered for its police crackdown on demonstrators, as is Seattle's World Trade Organization conference in 1999.
"The violence issue could lead people to go to McCain or lead people not to vote for Democrats," said Dana Fisher, a Columbia University sociology professor and an expert on mass political protest. The protesters themselves, she said, are less likely to vote "because they don't like the two-party system."
Range of protests due this week
Many smaller protests are scheduled here this week under an elaborate system the city has established. Each group has its own time and place, with specific parade routes leading to the Pepsi Center convention site or, on Thursday, Invesco Field, where Obama will deliver his acceptance speech to some 70,000 people.
The largest groups are the local anti-war organizations — Recreate 68 and the Alliance for Real Democracy, both of which planned rallies and marches Sunday to greet arriving delegates. The disunity worried some national antiwar leaders.
"The challenge is, will we be able to collectively rise to the occasion and move beyond our individual activities to deliver a collective statement," said Leslie Cagan, co-founder of United for Peace and Justice.
Police were taking no chances. The city has hosted Pope John Paul II, the Group of Eight, the Super Bowl and the World Series, but its last national political convention was exactly 100 years ago. It has set up holding cells for anyone arrested that have chain-link lids. "Hopefully, nobody will have to go there," said police spokesman Sonny Jackson.
The tight controls placed on protesters angered local organizers, who said they planned no violence. "Our goal is to have everything come off as peacefully and non-violently as possible," said Mark Cohen, an organizer for Recreate 68.
Other causes getting attention here this week include immigration, health care, women's equality, prisoners' rights, the environment, energy costs and legal marijuana. At Sunday's march, there were even protesters heralding militant Shiite leader Muqtada al-Sadr as well as independent presidential candidate Ralph Nader.
Democrats took the protests in stride. "We do recognize the importance of the freedoms protected by the First Amendment," said Natalie Wyeth, spokeswoman for the Democratic convention.