As angry demonstrators clogged streets and shut down highways and bridges in New York, Chicago and San Francisco on Thursday, New York City Police Commissioner Raymond Kelly said that this generation of antiwar protesters has become particularly vicious. "There is a hard core group.... who are particularly nasty," Commissioner Kelly told WOR Radio's Bob Grant. "I've noticed this and I've been around a long time. It's kind of like the Vietnam war protests." Kelly complained that the anti-Iraq war protesters had engaged in acts like "spitting on police officers, cursing at them, trying to instigate them." He added, "It really...