Explainer

Tit for Tat

What’s a “proportionate” response?

Israeli soldiers on a boat

Amnesty International, the United Nations Human Rights Council, and the European Union are calling for an investigation into Israel’s attack on the Mavi Marmara. At issue is whether Israeli actions, which resulted in nine civilian deaths, violated the “basic principle” of proportionality, as German government spokesman Ulrich Wilhelm put it. Finland’s prime minister Vanhanen Hanen, for his part, noted that Israel uses disproportionate force all too often. The word “proportionality” gets thrown around a lot when Israel’s in the news. What does it really mean?

That’s subjective. There are two separate but related principles of proportionality—the first derived from jus ad bellum (the rules governing decisions to go to war), the second from jus in bello (the rules governing conduct during war). As for the first: Under the United Nations charter states have the right to self-defense, but defensive actions should not exceed necessity. Colloquially, that’s sometimes rendered as “Don’t bring a gun to a knife fight.” This formulation is somewhat misleading. The concept isn’t a mandate for tit-for-tat violence. States may deter future assaults aggressively, but they’re not supposed to launch a counterattack that’s radically incommensurate with the actual threat. If your enemy launches a few rockets at your capital city, you’re not supposed to respond with a carpet-bombing campaign. Yet there is no codified or universally accepted calculus (like one canon blast for every 10 gun shots) for determining which actions count as reasonable and necessary.

Once two or more parties are in the midst of an armed conflict, international humanitarian law requires a different sort of proportionality. Briefly, military commanders must take precautions to ensure that expected civilian losses from a given attack are proportionate to the military advantage it will confer. Again, there is no equation for exactly what sorts of losses are acceptable. Clearly, it’s not OK to take out a mid-level al-Qaida operative visiting a kindergarten while school is in session. But maybe it is OK to take out a munitions factory even if civilian janitors are in the building. Of vital importance here is whether the military commanders take reasonable precautions to reduce collateral damage, with an emphasis on their knowledge at the time of the operation (rather than after the fact). Did they check to see whether there’s a time of day when no janitors are around or just start bombing without due diligence?

In discussing the Israeli-Palestinian conflict, commentators sometimes confuse these two different concepts of proportionality, governed by different bodies of law. An Israeli attack on an obviously insignificant Gaza target that results in many civilian deaths would constitute a violation of the international humanitarian law of proportionality. But commentators may suggest that the war effort itself (rather than a particular act of war) is disproportionate and therefore in contravention of the U.N. charter. This confusion seems to pop up in an Ask Amnesty forum exchange from the 2009 action in Gaza. A reader asks “What is a ‘proportionate’ response to a terrorist group that deliberately puts civilians at risk by hiding among them and shooting rockets at other civilians?” and an Amnesty spokesperson answers “A proportionate response is one which does not involve the targeting of civilians or civilian objects. … International humanitarian law takes into account the legitimate military imperatives of warring parties. There is no justification for perpetrating serious violations of IHL.” So the reader seems to be wondering about the mandate for proportionality in the case of an attack (“shooting rockets at other civilians”), while the answer focuses on the reasonableness of particular military acts in the course of an armed conflict.

In the case of the Mavi Marmara, Ulrich Wilhelm and others seem primarily concerned with proportionality in the counterattack sense, rather than the military-advantage-vs.-civilians sense.   The specific legal document at play is the San Remo Manual on International Law, * which lays out that force may be used against a ship trying to breach a blockade so long as the force is necessary and proportionate. Organizations such as the Carter Center hold that even if the Israeli soldiers were defending themselves, their use of deadly force was uncalled for, and suggest that they could have used any number of nonlethal means—like tear gas or tasers—to contain the situation.

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Explainer thanksHrair Balian of the Carter Center andLaurie Blank of Emory’s International Humanitarian Law Clinic.

Correction, June 3, 2010: This article originally stated that the legal document at play in the case of the Mavi Marmara is the U.N. Convention on the Law of the Sea. The San Remo Manual on International Law is actually more pertinent. (Return to the corrected sentence.)

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