1) Reading about the "alleged" shooter Jared Loughner, it's hard for me to gin up anger towards him despite the evil act he's accused of. I suppose the reason is because of the complete irrationality of what he did--this isn't, say, a guy who committed murder to serve some material aim (stealing a wallet, say) or to fulfill a political goal (like the 9/11 hijackers) or some hateful end (such as someone who murders a person because of their race/ethnicity). The guy was so clearly off the deep end--or at least it appears that way now, an investigation may uncover more--that the whole thing is just sad. Here's a truly crazy, sad person whose brain was so off that he did something like this. And his mugshot just reinforces that.
2) Sarah Palin yet again reinforces what her critics have always said about her. Here she had a chance to display class and statesmanship, and if she is planning to run for Prez in 2012 (as many believe, though I have doubts she even wants that), this could be a chance to boost her ratings. Due to the shooting of a congresswoman that Palin had "targeted" for defeat last year, and due to Palin's gun imagery in her campaigning, the former VP candidate has been under the spotlight this past week. This was a chance for her to address that--to take an opportunity to call for greater civility in our political discourse, to express regret for having used unfortunate imagery that, while it did not lead to this shooting incident, was at least in poor taste. Instead, Sarah goes ahead and (a) spreads blame for all this across the political spectrum; (b) contradicts this point by noting that political discourse has always been violent, as debates used to be settled with dueling; and (c) made herself the victim, using the unfortunate phrase "blood libel", comparing (most likely unwittingly) her plight to that of medieval Jews who were blamed falsely for murdering Christian babies. Way to go, you class act!
3) Again, there just seems to be no way to prevent this sort of thing. Politicians are always going to trade down personal security in favor of access to voters, and even under the strictest gun control regime we cannot keep a determined person from getting a firearm. Can we pass some law preventing anyone from bringing a gun within 1000 feet of a federal official? Sure, but absent searching everyone who wants to get near their representative, this isn't going to do much.
4) This also illustrates how helpless we are in dealing with the mentally ill. Loughner had displayed a lot of signs over the years, though it seems the behavior only really looks that bad in retrospect. An antisocial person who rants on the Internet and has strained friendships, can't hold a job, unnerves others? Hell, that's half of society. Haven't you seen teenagers these days? Even when we're clear that someone has a problem there's no easy treatment. Had it not been for this incident, it's entirely possibly this guy would have just suffered along unnoticed.