International waters are infested with Somali Muslim Arab pirates and Indonesian Muslim pirates. Gaza declared war on Israel. At times of war... Remember WWII? Many battles on international waters. Israel has the right to defend agains next door jihadists. They want to be sure that weapons are not being smuggled. This is just propaganda, because basic goods are let through the border with Israel.. You know Arab Judenrein Gaza shares a border with Arab Egytp too, don't you? Why don't their cousins open their side of the border?
from the article: IDF vows to block 'Freedom Flotilla' aid convoy to Gaza