Israel's boarding of a flotilla of boats bearing humanitarian aid to blockaded Gaza ended with tragedy. The Israeli Navy forces boarded with ladders from helicopters and were not expecting hostilities. When people on one of the ships, mostly Turks, started attacking the boarders with metal rods and clubs, the Israelis opened fire, and some 10 people were killed.
What was this--miscommunication, an act of piracy, a legitimate act of self-defense, civil disobedience, or a "massacre" (as some of the Palestinian press have dubbed it)? I would say, none of the above. While Israel has a legitimate right to self-defense, which would justify it examining anything crossing its borders into Gaza for weapons which might be used against it, this attack took place in international waters, against ships bearing a white flag of peace. Israel warned the flotilla against the direct route to the Gaza coast that it was taking--most likely, the boats could have accepted being re-directed to the Israeli port and the goods would have been delivered (more or less what is happening, after last night's unpleasantries, and after the deportation of those Israel doesn't want around).
I would call it a criminally stupid overreaction to a deliberate provocation. The Israelis were not expecting arms (and none were found) in the fleet of boats--if they were, they would've planned an armed attack. The flotilla wasn't practicing satyagraha, they (some of them, anyway) wanted to fight to defend their right to make an unauthorized landing. There was a principle at stake, for both sides--the Israelis claim to have control over anything coming into Gaza, while their opponents deny that claim. That was what the fight was about.
The Israelis' claim is not backed by international law--they have no legitimate authority over Gaza. They have a treaty with Egypt to control anything coming in from that direction, and there are no other land routes into the "world's largest open-air prison" that do not go through Israel. The US tolerates the Israelis' unilateral declaration of blockade as a practical necessity, but it is not formally recognized, certainly not by the United Nations. The purpose of the blockade is to undermine Gaza's legitimately elected government (which is Hamas), and the Israelis claim it is working. So, they intentionally starve Gaza of all but the minimum required for bare survival. This is not a humane policy, and it will not stand up to the scrutiny of the world, which Israel has invited through an unwise, aggressive action.