FILE - In this Aug. 15, 1964 file photo, a demonstrator clutches his glasses as New York City police officers subdue him in Times Square in New York during a protest against U.S. actions in South Vietnam. Todd Gitlin said in his history of the era, "The Sixties: Years of Hope, Days of Rage": "There are times when an entire culture takes the shape of a single event, like rows of iron filings lined up by the force of a magnet. ... The educated young felt his call, projected their ideals onto him. His murder was felt as the implosion of plenitude, the tragedy of innocence. From the zeitgeist fantasy that everything was possible, it wasn't hard to flip over and conclude that nothing was." (AP Photo)