I don't think it makes much sense to talk about Israel, its actions, and its place in the world using the standard language of imperialism and geopolitics. Israel is both too anachronistic and too out in the lead on these things to say that they are controlled by the U.S., or the U.S.' attack dog in the region, or that the U.S. is acting as the bad cop to Europe's bad cop, or any of those geopolitical, vaguely conspiratorial, views of the world. Not that there's not some truth to all of them, but they raise more questions than anything, and look kind of silly.
Deleuze wrote an article (part of which is below) about the events of 1978 and one of his main points was that Israel was basically a laboratory for military and political techniques of how to deal with and benefit from terrorism. I don't think its role has changed much since then. Eyal Weizman <http://www.opendemocracy.net/article/legislative-attack> said that last year's, Gaza war was an experiment in what he called lawfare: using military operations to push against the principles of international law and making them more favorable to its needs; lawmaking by warmaking. I wonder if there's not something similar going on with flotilla attack: experimenting with what sort of military actions against humanitarian/aid groups it can get away with that will benefit its political aspirations. You can bet the U.S., Europe, and China, for starters, are watching the results.
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Gilles Deleuze, "Spoilers of Peace" This text originally appeared in Le Monde, April 7, 1978
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The Israeli-Palestinian conflict is a model that will determine how problems of terrorism will be dealt with elsewhere, even in Europe. The worldwide cooperation of States, and the worldwide organization of police and criminal proceedings, will necessarily lead to a classification extending to more and more people who will be considered virtual "terrorists." This situation is analogous to the Spanish Civil War, when Spain served as an experimental laboratory for a far more terrible future.
Today Israel is conducting an experiment. It has invented a model of repression that, once adapted, will profit other countries. There is great continuity in Israeli politics. Israel believes that the U.N. resolutions verbally condemning Israel in fact put it in the right. Israel has transformed the invitation to leave the occupied territories into the right to establish colonies there. It thinks sending an international peace-keeping force into Southern Lebanon is an excellent idea ... provided that this force, in the place of Israeli forces, transforms the region into a police zone, a desert of security. This conflict is a curious kind of blackmail, from which the whole world will never escape unless we lobby for the Palestinians to be recognized for what they are: "genuine partners" in peace talks. They are indeed at war, in a war they did not choose.