Foreign Affairs
In "The Gaza Blockade and International Law" University of Chicago law professor Eric Posner (WSJ subscriber only) notes the precedent for Israel's blockade of Gaza in the American Civil War--the Union's seizing of Confederate ships on the high seas. Israel does not recognize Gaza's sovereignty. "... Israel's legal position is reasonable, and it has precedent. During the U.S. Civil War, the Union claimed to blockade the Confederacy while at the same time maintaining that the Confederacy was not a sovereign state but an agent of insurrection." A closely divided Supreme Court approved the seizures, suggesting "a certain latitude for countries to use blockades against internal as well as external enemies."
In an important sense, the criticism of Israel is a criticism of past American practice as well. In looking to our self-interest in the Middle East, Americans should recall our own history.
Part of the reason why the Union worked so hard diplomatically to convince other states not to acknowledge the independence of the Confederacy was because the rules at sea would change if Confederate ships belonged to an independent country. Also, because of the historic defence by the United States of neutral rights for ships of third-party countries, the basis for the U.S. to blockade the Confederacy depended on countries like Britain not seeing the South as a country at war with the North, but as a rebellious province and essentially volunteering not to ship to the South.
This looks like a legal grey area to me, since Israel is blockading an enclave that is neither a part of Israel nor a sovereign state. Unlike in the Civil War, Israel doesn't regard Gaza as part of Israel (and neither does anyone else in the world) and is not trying to re-integrate a rebellious province into its political life. While no historical analogy is perfect, if you want to look back into America's history, I think a better example would be the War of 1812, with Turkey now in the position of the United States then. Why, with America's historic commitment to neutral rights for shipping, should we not regard Israel's killing of Turkish citizens as a violation of Turkey's neutral rights, especially if they were not shipping war materiel?
Peter: but why not go further and (as much of the West has done) compare the Israeli action with German sinking of American ships going to Britain in WW I and WW II (prior to declarations of war)? As Posner argues, the boarding of the ships for the purpose of searching for war materiel is justifiable under international law. The stopping and boarding was not done for the purpose of killling the Turks.