Argument: Israeli blockade of Gaza is legal during conflict with Hamas
Leslie Gelb. "Israel was right." The Daily Beast. May 31, 2010: "Regarding international law, blockades are quite legal. The United States and Britain were at war with Germany and Japan and blockaded them. I can't remember international lawyers saying those blockades were illegal—even though they took place on the high seas in international waters. There would be a general violation only if the hostile actions against the ships took place in waters under the jurisdiction of another sovereign state. Thus, for example, if the Israelis stopped the ships in Egyptian waters, that would have been a violation.
[...] the overriding facts remain that Gazan leaders proclaim their goal is to destroy Israel, have tried for years to do so by missile attacks and terrorism, and that Israel has every right to protect itself under international law, including by blockades in international waters."
"Israel obeyed international law: Legally, the Gaza flotilla conflict is an open-and-shut case". By Alan Dershowitz. NY Daily News. "The legality of blockades as a response to acts of war is not subject to serious doubt. When the United States blockaded Cuba during the missile crisis, the State Department issued an opinion declaring the blockade to be lawful. This despite the fact that Cuba had not engaged in any act of belligerence against the United States. Other nations have similarly enforced naval blockades to assure their own security."
"The Gaza Flotilla and the Maritime Blockade of Gaza ." Z Street. May 31, 2010: "1. A maritime blockade is in effect off the coast of Gaza. Such blockade has been imposed, as Israel is currently in a state of armed conflict with the Hamas regime that controls Gaza, which has repeatedly bombed civilian targets in Israel with weapons that have been smuggled into Gaza via the sea.
2. Maritime blockades are a legitimate and recognized measure under international law that may be implemented as part of an armed conflict at sea.
3. A blockade may be imposed at sea, including in international waters, so long as it does not bar access to the ports and coasts of neutral States.
4. The naval manuals of several western countries, including the US and England recognize the maritime blockade as an effective naval measure and set forth the various criteria that make a blockade valid, including the requirement of give due notice of the existence of the blockade. 5. In this vein, it should be noted that Israel publicized the existence of the blockade and the precise coordinates of such by means of the accepted international professional maritime channels. Israel also provided appropriate notification to the affected governments and to the organizers of the Gaza protest flotilla. Moreover, in real time, the ships participating in the protest flotilla were warned repeatedly that a maritime blockade is in effect. Here, it should be noted that under customary law, knowledge of the blockade may be presumed once a blockade has been declared and appropriate notification has been granted, as above. Under international maritime law, when a maritime blockade is in effect, no boats can enter the blockaded area. That includes both civilian and enemy vessels.
8. A State may take action to enforce a blockade. Any vessel that violates or attempts to violate a maritime blockade may be captured or even attacked under international law. The US Commander's Handbook on the Law of Naval Operations sets forth that a vessel is considered to be in attempt to breach a blockade from the time the vessel leaves its port with the intention of evading the blockade.
9. Here we should note that the protesters indicated their clear intention to violate the blockade by means of written and oral statements. Moreover, the route of these vessels indicated their clear intention to violate the blockade in violation of international law.
10. Given the protesters explicit intention to violate the naval blockade, Israel exercised its right under international law to enforce the blockade. It should be noted that prior to undertaking enforcement measures, explicit warnings were relayed directly to the captains of the vessels, expressing Israel's intent to exercise its right to enforce the blockade.
11. Israel had attempted to take control of the vessels participating in the flotilla by peaceful means and in an orderly fashion in order to enforce the blockade. Given the large number of vessels participating in the flotilla, an operational decision was made to undertake measures to enforce the blockade a certain distance from the area of the blockade.
12. Israeli personnel attempting to enforce the blockade were met with violence by the protesters and acted in self defense to fend off such attacks. "
Roz Rothstein, chief executive of StandWithUs, said in a telephone interview: "We're very concerned about Hamas and weapons coming to Hamas. What you saw was Israel trying to protect its citizens."
Shikhar Singh. "Yes, Legally and Morally." "WSJIDEBATE: Israel’s Gaza Blockade Is Justified." June 8th, 2010: "Were Israel’s security concerns legitimate? Let’s be clear about certain basic facts: this is a disturbed topography we are talking about— one engaged in an intractable conflict for decades. There is an oft exaggerated but yet undeniable “existentialist threat” to Israel (and Palestine, as some would argue). In recent months, an internationally listed terrorist group (Hamas) has seized power in the Gaza strip and used the area under its control to direct rocket and missile attacks against Israel. This is unambiguous provocation, something that fuelled an Israeli military response and ultimately an economic blockade of Gaza."
Eric Posner. "The Gaza Blockade and International Law." Wall Street Journal. June 4, 2010: "The catch here is the meaning of "armed conflict." Traditionally, armed conflict can take place only between sovereign states. If Gaza were clearly a sovereign state, then Israel would be at war with Gaza and the blockade would be lawful. If, however, Gaza were just a part of Israel, Israel would have the right to control its borders— but not by intercepting foreign ships outside its 12-mile territorial sea or contiguous zone.
Gaza is not a sovereign state (although it has its own government, controlled by Hamas) and is not a part of Israel or of any other state. Its status is ambiguous, and so too is the nature of the armed conflict between Israel and Hamas. Thus there is no clear answer to the question whether the blockade is lawful.
However, the traditional idea of armed conflict involving only sovereign states has long given way to a looser definition that includes some conflicts between states and nonstate actors. The international rules governing blockades attempt to balance belligerents' interest in security and other countries' economic interests in shipping. During war, security interests prevail.
War-like conditions certainly exist between Israel and Hamas. And because Israel intercepts only self-identified blockade runners, its actions have little impact on neutral shipping. This balance is reflected in the traditional privilege of states to capture foreign pirates on the high seas.
So 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."