Analysis: The bombing of ISIS oil fields and what it means for Israel

At last, the Obama administration relented. For months, critics had called for the United States to bomb Islamic State oil fields. Not just the refineries that prepared the oil used by IS fighters, but the oil fields themselves, from which IS exports crude and makes money. Those oil fields are “legitimate targets for coalition attacks,” argued commentator Amir Taheri. “Bomb the hell out of” the oil fields, brayed US presidential candidate Donald Trump.In late October, the Pentagon launched Operation Tidal Wave II – in which US B-1 bombers did just that.The objective? To deprive the world’s most notorious terrorist organization of the funding and power that oil revenues have given it. Dry up that tap of funding, the theory goes, and starve IS of what it needs to survive.As a matter of military strategy, that sounds logical enough: Hit the enemy’s center of gravity and force it to surrender.As a matter of international law, though, the case has been anything but clear.Until now, both states and experts have disputed whether a party to an armed conflict may attack so-called “war-sustaining” economic targets. Now, the United States is doing so, and no one is protesting. Hitting the IS oil fields, it seems, is allowed. For Israel, that has important implications for how future conflicts are fought.The legal debate arises because the IS oil fields, and targets like them, are not necessarily the traditional military-oriented targets allowed under international humanitarian law. Under the legal principle of distinction, a party may target so-called “military objectives” but not “civilian objects.” The idea is that an army should aim to hit the other side’s soldiers and weapons, not its shopping malls and kindergartens. These extreme examples may be clear, but, like many legal principles, the distinction is harder to apply in some cases.For example, let’s say a party uses proceeds from a particular factory or farm to finance its war effort. To qualify as a military objective, that factory or farm must “make an effective contribution to military action.” Most states and most commentators have said that factories and farms such as these fail to meet that test.To make an “effective contribution,” they have said, an object must have a more direct military connection: a tank, a base, a weapons system, a launching site. A factory or farm – or oil field – is too far removed from the war-fighting itself to make an effective military contribution, even if profits from it are used to fund the war.With this, the US has long disagreed.The US military has held that a “war-sustaining” target is fair game. As put in its most recent manual on the laws of war, the US military does not require a potential target to “provide immediate tactical or operational gains” or “make an effective contribution to a specific military operation.”“Rather,” the manual explains, “the object’s effective contribution to the war-fighting or war-sustaining capability of an opposing force is sufficient.”This position from the US is not new.For at least two decades, the US military has argued it could hit economic targets.What is new is that the US military is now applying its policy brashly on the battlefield, and states seem not to be objecting. In international law, this can be important. International law is based on state practice. If states watch US attacks against IS oil fields and do not object, their silence can help to define and establish the law.That law applies equally for, and against, all parties. Some might think that because IS is so notorious, types of attacks might be permitted against it that would not be allowed against others. But international humanitarian law (i.e., the law of war) does not work that way. Under the law, once an armed conflict starts, all parties are bound by the same rules on who, where, when, and how they can attack. If the US can attack “war-sustaining” economic targets belonging to IS, then IS can do the same to the US. Or Russia could do the same to IS. Or IS to Russia. Or Israel to Hezbollah, or Hezbollah to Israel.The attacks against the IS oil fields – and the international assent to them – serve as precedent not only in that conflict but in other conflicts. If the law permits the US to attack war-sustaining economic objects belonging to IS, then if and when Israel is in an armed conflict, Israel, too, may legally attack such targets.That could change the way Israeli planners approach future conflicts. In past rounds of fighting, Israel’s military brass has come under pressure to expand the bank of potential targets. Hawks have called for a more aggressive bombing campaign, while military lawyers have enforced the restrictions imposed by the law. Some of the potential targets at issue were economic objects that helped sustain the enemy’s war efforts. Those targets could now get a green light from military lawyers.Questions would still arise about potential civilian casualties. Even if the economic targets meet the standard for “distinction” – that the potential targets themselves are “military objectives” – the potential attacks must also meet the standards of “proportionality” in civilian casualties and harm to civilian objects that might be caused.Attacking these targets also might not be a good idea, at least not in all cases.For reasons of strategy or tactics, the IDF might decide to hold its fire or to direct it elsewhere. Moreover, if the rules on war-sustaining economic targets have changed for Israel, so, too, have they changed for Israel’s adversaries. Hezbollah and Hamas, too, could cite the strikes on IS oil fields as precedent for striking economic targets in Israel. So the evolving rules might prove a mixed blessing.Still, the attacks on the IS oil fields matter for international law, and the effects will be felt as soon as Israel’s next conflict.A wider range of targets might now be eligible for Israel’s target list. And Hezbollah or Hamas might have legitimacy to expand its set of targets, too.US Defense Secretary Ashton Carter may not have boasted too loudly about the IS oil fields strategy. And states around the world might have greeted the move with silence. But the muted response must not fool us. Loosening restrictions on war-sustaining economic targets will change the laws on how future conflicts are fought. Israel will feel the effects, for better or worse.

The author is a research fellow at the Institute for National Security Studies in Tel Aviv.