Because, apparently, the commandos roughed up the peaceful protesters on the other ships. And then, later, they got roughed up again in the Israeli prison:
Adam Shapiro, one of the organizers, also reminds us of something that too many people are ignoring: we have footage of the commandos firing live ammunition as they boarded. The passengers were defending themselves.
Not that it matters. Both the Dems and the Republicans would back Israel no matter how brutal the crime, and no matter how terrible the international isolation that follows. The Dems are especially showing that—like with the Health Care bill—there is no line that you could cross that would cause them to break ranks.
Morals don't matter. Ethics don't matter. Humanitarian concerns don't matter. NOTHING matters. All that they care about is sticking with the party line.