Team Obama, having labelled town hall opponents of health care as violent mobs of extremists, have now instructed their supporters to turn violent. Top White House officials counseled Democratic senators Thursday on coping with disruptions at public events on health care this summer, officials said, and promised the party and allies would respond with twice the force if any individual lawmaker is criticized in television advertising. Until now, the protests have been entirely peaceful, but the Obama administration’s decision to encourage violent clashes is designed to reinforce their depiction of opponents of health care as violent extremists. The media will...