From another reader:

The attack on the soldier was disgusting and deserves publicity. But your correspondent’s attempt to generalize one attack on one soldier to smear the entire left is wrong and unfair. The article didn’t mention any other similar attacks, so, thankfully, this does not appear to be a trend.
The correspondent’s logic is as valid as the logic in some of the letters to the editor I sometimes see: “Someone tore down my Kerry (Bush) yeard sign. Bush (Kerry) supporters are all thugs who hate the First Amendment.”
I hope they catch the bastard that did this, but this was the act of one criminal, not a political party or movement.