It does sound like there might have been some kind of violent response from the activists on the boat, and the Israeli military is claiming its forces encountered “live fire and light weaponry including knives and clubs."
But the international response has been swift. Turkey has recalled its ambassador and warned of "consequences," U.N. Secretary-General Ban Ki-moon has called for an investigation, European governments have expressed shock, and I imagine thousands of outside observers like me are wondering just what possessed the Israeli government to risk such an outcome when it sent naval commandoes to board the vessel.
As Haaretz's Amos Harel puts it, "The damage that Israel has caused itself internationally can hardly be exaggerated." Harel warns that the rumored presence of an Israeli Arab activist among the victims could lead to riots and perhaps even "a third intifada."
Another liberal Haaretz commentator, Bradley Burston, comments, "We are no longer defending Israel. We are now defending the siege. The siege itself is becoming Israel's Vietnam."