Has the shooting of Congresswoman Gabrielle Giffords in Tucson Saturday made Americans more worried that opponents of Barack Obama’s policies will turn to violence? Actually, a little less so, according to pollster Scott Rasmussen. When he asked the question last March, 53% of respondents said they were very or somewhat worried. When he asked the question again on Sunday and Monday, after the Tucson shooting, 45% said they were very or somewhat worried. Not the response I would have expected.