Like it or not, agree with it or not, Israel's blockade is legal. Breaking such a blockade isn't. The fact that the incident happened in international waters is completley irrelevant. The flotilla expressed their into to sail to gaza many times. Under the Hague conventions when a civilian attacks a soldier they lose their civilian status and become classified as a combatant.
U.S. says working on initiative to de-escalate Syria fighting, with focus on Aleppo (Reuters)