The loss of life on the flotilla attempting to move from Cyprus to Gaza is tragic, but it was also completely avoidable. This is a topic certain to inflame passions, but there were a few points I felt I had to make.
Gaza is under a declared blockade; one declared not by Israel alone, but rather by Israel and Egypt. While Israeli warships and troops carried out the blockade in this instance it is important to remember that a Palestinian ally supports the blockade. The flotilla's organizers refused to follow the protocol of the blockade, docking in either Egypt or Israel to have their cargo inspected and then delivered overland to Gaza. They wanted to make a statement, and they did that.
Obviously the primary focus of the blockade is weapons smuggling. Currently what is known as dual-use material is also restricted from shipment to Gaza under the terms of the blockade, however, as a result of the risk of it being used to support violence and terrorism. Piping and concrete are harmless in and of themselves, but they can become rockets and bunkers. As it stands today the blockade is a hardship on the people of Gaza, but food and medicine are exempt from the blockade and it doesn't add unduly to the humanitarian crisis that is Gaza.
The terms of the Camp David agreements removed Israeli troops from Gaza. they also forbade heavy weaponry to the Palestinian government of Gaza, something that Hamas has been reluctant at best to comply with. (Hence the blockade) Until Hamas realizes that giving up certain kinds of weaponry is one of the prices for peace, just as Egypt is not allowed heavy weaponry and more than a certain number of light soldiers in the Sinai, then the peace process will remain stalled. Israel, of course, needs to make concessions as well, with the most egregious violation on its part of the peace terms being the continued building of settlements on Palestinian land. This is, however, a separate issue.
Running a declared blockade means that you know there is a real possibility of a military response, and by declaring your intention and timeline beforehand you are basically fishing for one. Last night 3 Israeli naval vessels intercepted the flotilla, and presumably were unable to convince them to turn around or dock for inspection in accordance with the blockade. These vessels rightly decided that sinking the ships would be excessive, and elected to use a much lower scale of force. Interestingly the information I've seen indicates that all vessels complied without violence except one, so we'll have to see whether that case involved excessive force or real provocation. Sadly the facts may actually matter very little as the overwhelming majority of people will simply fit this episode into whichever pre-conceived framework they want to.
As a final thought there will be calls for the UN to take action against Israel as a result of this, and the question that I have is why did Israel's opponents give up on the UN to pressure Israel and Egypt to take down the blockade?