It’s clear for lots of reasons—political, economic, strategic, electoral, opportunistic, moral, and simply sensible, to name a few—that President Obama has no desire to get drawn back into the Iraq war. So why is he bombing Islamist insurgents in the Kurdish region of Iraq and saying he might keep doing so for months? Because what he’s doing has nothing to do with getting drawn back into the Iraq war.

This seems a paradox, to say the least, but stick with me for a minute. We can all agree that “the Iraq war” refers to the period from 2003-11, when a U.S.-led coalition invaded Iraq, ousted the central Baghdad government, and dismantled all bodies of authority, thus hurling most of the country into sectarian warfare, which American commanders tried to suppress, first through crude, brutal occupation, then (in 2007) through clever counterinsurgency techniques, which played the sectarian factions off one another, vastly reducing the violence and forging a provisional truce.

However, even the advocates of this new strategy, such as Gen. David Petraeus, said all along that the benefits would be temporary at best; that all U.S. forces could do was provide “breathing space” for Iraq’s political factions to get their act together.

After American troops came home (under the terms of a 2008 treaty signed by George W. Bush at the insistence of Iraq’s parliament), it soon became clear that Iraq’s Shiite prime minister, Nouri al-Maliki had no desire to get his act together and sustain the truce with his Sunni rivals; in fact, he stepped up his persecution against them—and sectarian war re-erupted.

This is the Iraq war that neither President Obama nor any sentient American should want to re-enter. Obama’s airstrikes against the Islamists’ holdings in Kurdistan are something different.

Note that three paragraphs ago, in my mini-summary of the Iraq war, I noted that the 2003 ouster of Saddam Hussein’s regime and the dismantlement of all his ministries hurled “most of the country into sectarian warfare.” (The emphasis, this time, is added.) The one area of Iraq that remained nearly immune from the chaos—the one area that U.S. authorities deemed “stable” through most of the occupation—was the northern area known as Kurdistan, home to roughly 6 million Kurds.

This is true, despite Kurdistan’s multiethnic population (mainly Muslims but also Yazidis, the Yarsan, Christians, and Jews) and its various conflicts over the decades with Baghdad. The main reason for Kurdistan’s stability is that in 1970 the U.S. and Iraqi governments decreed it an autonomous area. More relevant still, after the 1991 Gulf War, the U.N. Security Council, in, Resolution 688, declared the area a “safe haven” to protect Kurds from Saddam Hussein’s wrath. (He had killed thousands of Kurds with chemical weapons during the Iran-Iraq war in the 1980s.) And the United States agreed to enforce the resolution with a “no-fly zone.” (In other words, all Iraqi planes trying to fly over Kurdish territory would be shot down by U.S. air or naval power.)

Under this protection, Kurdistan has thrived. Its per capita income exceeds the rest of Iraq’s by 50 percent, it has free-trade zones with Turkey and Iran (both of which were once rivals or enemies), and it has solid relations with many Western companies.

The Kurds’ growing wealth has sired tensions too. As Sunni-Shiite violence has turned Iraq into a borderline “failed state,” the Kurds have started making their own deals with oil companies and made moves toward their centurylong aspirations of complete independence (which the French and British colonialists thwarted after World War I by divvying Kurdish territory among the peripheries of Iraq, Turkey, Syria, and Iran). This would deny Baghdad and Iraq’s Sunni Arabs of much oil revenue. Still, it’s become very clear that, if Iraq—whether as a centralized state or a loose federation—has any hopes of ever becoming stable, much less democratic, a thriving Kurdistan must be part of it, even a model for it.

When ISIS (now calling itself the Islamic State, or IS) crossed into Iraq in June, many in the West expressed worry but not enough to do a lot about it. First, ISIS seemed pretty small. Second, few realized that—under Maliki’s corrupt leadership—much of the Iraqi army had become a hollow shell of its former shelf. Third, ISIS was playing on the hostility of many Sunnis to Maliki’s Shiite government, so most Western leaders said the only way to solve the problem was for the Iraqis to form a new, more inclusive government; meanwhile, if we defended what was seen as an oppressive Shiite government, we would be viewed as “Maliki’s air force” and drive still more Sunnis into ISIS’s ranks.

Finally, and most pertinent in this context, it was assumed—and, at the outset, affirmed—that the Kurdish peshmerga could defend itself if ISIS moved into Kurdistan.

President Obama’s Aug. 11 announcement of airstrikes over Kurdistan and increased military shipments followed the first signs that ISIS could challenge the peshmerga after all.

In other words, Obama’s moves do not amount to a resumption of the Iraq war but rather a necessary response, not only to a humanitarian crisis but to a mortal danger facing a vital ally.