Toning down the political rhetoric is the issue of the day, but popular conservatives don't seem to be the problem here. Our shooter wasn't saying anything about Beck or Palin or Rush or any of the usual suspects of the right.Rock and rap have nihilistic wings that seemed to have been more an inspiration than any media talker, but there aren't political points to be made by bashing them.
Demonizing your foes is not cool, given that the foe isn't usually the Devil himself. However, that isn't the problem; most murders of this type are done by people who aren't emotionally playing with a full deck and need help.
I'm not sure if the tone of our political discussions are going to change the number of attacks on public officials. Oklahoma City is about the only major piece of political terrorism that was right of center. Most everything else was either crazed (both shots at Ford, Reagan and Tuscon) or of the left (both Kennedies and Truman) with only King's assassination being a "right-wing" thing if you can chalk up racism as a conservative thing.
It doesn't seem that our shooter in Tuscon was coherently conservative; he seemed of the left more than of the right but with an anarchic, nihilistic streak that was more psychotic than political. The solution there would be to do more to get edgy folks into psych treatment sooner, but civil liberties issues crop up there, as it's hard to deem folks to be a danger to others before they actually act out on their thoughts.
Such aggressive treatment of violent-leaning personalities would require spending more resources on mental health and making the laws in that area less libertarian so to make it easier to force marginal folks into treatment. That will tick off both sides of the aisle, as it spends more money and makes the ACLU types nervous.