The US announced a major escalation in Iraq on Sunday. In a letter to Congress, President Obama said he would launch airstrikes in support of Iraqi forces fighting to reclaim the Mosul dam from the Islamic State (ISIS).
The key phrase needed to understand why this is a big deal isn't "Mosul dam" — it's "Iraqi forces." In the White House's press release, that's defined as "Iraqi Security Forces," the name for Iraq's central military rather than the Kurdish fighters, which the US was already backing with airpower. That opens the door to a much wider military campaign: one aimed at destroying ISIS entirely, not merely limiting its advance.
It's a strange situation. While targeting ISIS forces around the Mosul Dam is smart, the administration is pushing into potentially dangerous territory; the risk of entanglement and escalation is high.
Why this escalation is such a big deal
By explicitly authorizing airstrikes supporting Iraqi government forces, and not just the Kurdish peshmerga, Obama crossed an informal line he had previously held: don't help the Iraqi government until there's major political reform in Baghdad. That standard, it seems, no longer holds.
This is a point Obama has been clear on since June. He'd authorized strikes only in defense of Kurdish territory in northeastern Iraq and to save the members of the Yazidi minority trapped on a mountain by ISIS forces. "The US is not simply going to involve itself in a military action in the absence of a political plan by the Iraqis," Obama said in a June 13 address. He was more blunt in an August 8th statement, saying "the nature of this problem is not one our military can solve."
Now that Obama is willing to support Iraqi central government offensives anyway, this could escalate uncontrollably. The US military identifies individual ISIS targets around the country that the US could hit. Each, on its own terms, might make sense, as does, for example, the Mosul dam.
Gradually, the definition of a target worth hitting could expand, especially as the Iraqi army starts leading its own offensives to re-take ISIS-held territory. That would have the US following the Iraqi government's lead. Meanwhile, ISIS will likely adapt its tactics, focusing on hunkering down in towns and cities where US airpower is less effective and more likely to cause serious collateral damage.
After all, it took months of difficult, on-the-ground, door-to-door US-supported counterinsurgency to defeat al-Qaeda in Iraq, ISIS's predecessor in Sunni Iraq. Firing from the air, the US could become sucked into in a bloody campaign against ISIS that won't destroy the group, with the real issue — Iraqi political reform — falling by the wayside.
But the US is escalating for a good short-term reason: retaking the Mosul dam
The risk of escalation, though, has to be weighed against the benefits from the specific Mosul dam campaign. And those aren't trivial.
The Mosul dam sits just north of Mosul, Iraq's second-largest city currently controlled by ISIS. It provides over a gigawatt of power, irrigates farmland in western Iraq, and, if broken, it could unleash potentially catastrophic flooding from the Tigris River as far south as Baghdad. According to a 2007 American estimate, a broken Mosul Dam would mean 65 feet of standing water in Mosul.
So long as ISIS controls the Mosul dam, it could threaten civilian populations around the area. And the difficult-to-maintain dam could simply fall apart without high-quality maintenance.
The US campaign has helped push ISIS back. Since Obama's announcement on Sunday, a joint Iraqi government and Kurdish offensive has moved swiftly toward the dam. By Monday morning, Iraqi army forces were already claiming to have retaken it. US officials were more cautious, telling the Washington Post that fully clearing the dam would take time; ISIS had scattered improvised explosive devices (IEDs) around the area. As late as 8 a.m. EST on Monday, some reporters on the ground were still hearing airstrikes near the dam.
US airstrikes appeared to have played a big role: they targeted ISIS checkpoints and vehicles that could have cut off the advance towards the dam. They also cleared the way for local ground forces that might otherwise have difficulty destroying the armored vehicles ISIS has managed to capture. So while Obama opened the door to escalation, this specific campaign — on its own terms — appears to be working.
Is escalation inevitable?
Will this limited, defensible campaign escalate to something wider and more dangerous? At this point, that's troublingly hard to say.
The biggest barrier to this worst-case scenario may be Obama's own instincts. The president is in office in significant part because he opposed and wanted to end the Iraq war, and is deeply skeptical of any escalation there. But it's hard to say how much this would hold: Obama swore off ground troops in combat, and then came very close to authorizing a mission would put US troops in harm's way.
Securing the Mosul Dam made sense. But the US airstrikes required to do it set a potentially dangerous precedent.