The Islamic militants reportedly expanded their drive near Iraqi Kurdistan Saturday despite two U.S. airstrikes aimed at mortar positions and a seven-vehicle convoy to stop the advance on Kurdish capital of Irbil.

The Wall Street Journal reported that the militants appear to have their sights on connecting towns seized along the Kurdish-control territory. The most recent town to be seized was identified as Sheikhan…

Kamil Amin, the spokesman for Iraq’s Human Rights Ministry, said hundreds of Yazidi women below the age of 35 are being held in schools in Iraq’s second largest city, Mosul. He said the ministry learned of the captives from their families.

“We think that the terrorists by now consider them slaves and they have vicious plans for them,” Amin told The Associated Press. “We think that these women are going to be used in demeaning ways by those terrorists to satisfy their animalistic urges in a way that contradicts all the human and Islamic values.”

The head of the Senate Intelligence Committee on Friday said the extremist group the Islamic State in Iraq and Syria (ISIS or ISIL) must be confronted forcefully by the U.S., though she stopped short of calling for boots on the ground.

“It takes an army to defeat an army, and I believe that we either confront ISIL now or we will be forced to deal with an even stronger enemy in the future,” Sen. Dianne Feinstein (D-Calif.) said in a statement…

“Inaction is no longer an option,” according to Feinstein.

Thursday morning, the urgency to act in Iraq became clear: Obama’s advisers warned that there would likely be a genocide.

“I had not heard the word ‘genocide’ used in the Situation Room before,” the official said. “That word has a lot of weight.”…

“While we have faced many difficult humanitarian challenges, this was in a different category,” the official said. “This was qualitatively different from even the awful things we have confronted in different parts of the region because of the targeted nature, the scale of it, the fact this is a whole people. That kind of shakes you up, gets your attention.”

As the tension mounted in Washington, a parallel drama was playing out in Erbil. Kurdish forces who had been fighting the militants in three nearby Christian villages abruptly fell back toward the gates of the city, fanning fears that the city might soon fall. By Thursday morning, people were thronging the airport, desperate for flights out of town.

“The situation near Erbil was becoming more dire than anyone expected,” said a senior administration official, speaking on the condition of anonymity to describe the White House’s internal deliberations. “We didn’t want another Benghazi.”…

As if that were not enough, the militants had seized a critical dam in Mosul, which controls water levels on the Tigris River as far south as Baghdad. The capture of the dam shook Kurdish officials and fueled the sense of crisis during Thursday’s meetings, with officials worried that the militants could either blow it up or use it to cut off water supplies or as a bargaining chip in negotiating anything they wanted.

“That was one of the trip wires we looked at,” said another senior official. “We look at that dam as a potential threat to our embassy in Baghdad.”

While Mr. Obama said in a recent interview with The New York Times that the United States is not going to allow ISIS to create a caliphate that runs through Syria and Iraq, and spoke generally of his interest in working with “partners on the ground,” he has yet to articulate a detailed and systemic strategy for rolling back ISIS’ gains in the region.

In remarks on Saturday before departing for vacation, Mr. Obama acknowledged that ISIS gains in recent months had been “more rapid than the intelligence estimates and, I think, the expectations of policymakers.”…

A senior Kurdish official, who asked not to be named because he was discussing internal deliberations, said Saturday that the Kurdish authorities had asked the Obama administration several weeks ago to provide ammunition, sniper rifles, machine guns, mortars, vehicles and other equipment for their pesh merga fighters. Though the Iraqi government had recently provided some ammunition, he said, the Americans were still assessing the Kurdish request. “Pesh merga forces were forced to withdraw from engagements with ISIS forces because they ran out of ammunition,” said Michael D. Barbero, a retired Army lieutenant general who helped train Iraqi forces from 2009-11. “We should expedite this support to them.”

The Obama administration moved quickly this week to try to defend U.S. personnel from an impending advance from the terrorist group ISIS – an offensive that caught the President and his advisers off-guard, and forced him to reconsider his long-standing opposition to new military action in Iraq. But Obama still has not decided on, much less put into motion, any plan to stem ISIS’s expansion, despite having committed military forces…

The terror group’s push towards Erbil isn’t the first ISIS offensive that’s surprised Obama and his advisers. The administration’s slow response to ISIS’s quick advances in both Iraq and Syria is well documented. The White House ignored several warnings before ISIS took over Mosul earlier this summer. And the administration didn’t respond when moderate Syrian rebels warned that ISIS was about to take the strategic border town of Der al Zour.

According to sources close to the discussions, President Obama resisted using military force again in Iraq both because he did not feel confident there was sufficient intelligence on the ground. He was also reluctant to reverse the full pullout of combat forces in Iraq, which fulfilled a key campaign promise.

Yet by the White House’s own account, the measures ordered by Mr. Obama are not intended to defeat the Islamic State or even to stop its bloody advances in most of the region. Instead they are limited to protecting two cities where U.S. personnel are stationed and one mass of refugees. The hundreds of thousands of people in Syria, Lebanon and elsewhere threatened by the al-Qaeda forces will receive no U.S. protection. Nor will the terrorists’ hold over the areas they already control, including the large city of Mosul and nearby oil fields, be tested by U.S. airpower…

It’s past time for Mr. Obama to set aside a policy that is both minimalist and unrealistic. The United States should offer sustained military support to friendly forces that fight the Islamic State, beginning with the Kurds and including moderate Syrian rebels and Iraqi Sunni tribesmen. It should seek to erode the Islamic State’s military power as much as possible with airstrikes. It should not press for a new Iraqi government unless Shiite leaders and their Iranian sponsors agree to a fundamental restructuring of power. And it should forge a political and diplomatic strategy that encompasses both Iraq and Syria and their interrelated conflicts. The primary aim should not be to minimize U.S. involvement — as Mr. Obama would have it — but to defeat the forces that are destroying the region.

But with Obama’s latest decision to launch airstrikes against the Islamic State in the Levant (ISIL or ISIS), the Obama Doctrine has now come into focus: pretend to give a damn about suffering of innocents when it hits the headlines, ignore it the rest of the time…

It has been the case in Ukraine, where Vladimir Putin has annexed Crimea and invaded eastern Ukraine. Obama has expressed outrage; Putin has scoffed, and his rebel forces have shot down a passenger airliner, to approximately zero effective action from the West.

It has been the case in Nigeria, where after expressing upset over Boko Haram’s kidnapping of innocent girls and ensuring that the State Department endorse the “power of hashtag,” the Obama administration has done precisely nothing…

Now, Obama has done the same in Iraq. He will drop a few bombs. He will bluster. Then the world’s attention will turn to some other crisis, and Obama will blithely move on, leaving erstwhile allies to die.

As I have learned myself very painfully, there is an enormous amount the United States cannot do. It cannot solve Iraq’s political problems. It may not even be able to hold Iraq together. It cannot solve the horror in Syria. It cannot defeat the Taliban. It cannot stop Libya from descending into anarchy. But it can save the people in the Sinjar Mountains, both by dropping supplies to keep them alive, and by bombing ISIS so Kurdish forces can retake the areas nearby. And in so doing, it can stop genocide. Thankfully, Obama is doing just that…

It’s a risk worth taking, in part because in Iraq today, as in Southeast Asia four decades ago, we are culpable. Were it not for our war, and the anarchy it has bred, the Yazidis would likely not be facing imminent death. The reasons Americans want to turn away from Iraq are precisely the reasons we should not.

The impulse toward humanitarian intervention is dangerous. It can easily become hubristic. It can easily be exploited. Its means—which involve state violence—can often undermine its goals. But if crusades are dangerous, indifference is dangerous too. As sick as Americans are of the Middle East, as alien and hopeless as it seems today, we still have moral obligations there, less because we are Americans than because we are human beings.

The stronger moral obligation flows from two realities. First, this humanitarian crisis is one our actions directly helped create: The cleansing of Christians, Yezidis and other religious minorities began in the chaos following our invasion of Iraq, and it has taken a more ruthless turn because ISIS profited from the fallout from our too-swift 2011 withdrawal. (Indeed, it’s often using American-made weapons to harry, persecute and kill.)

Second, ISIS represents a more distinctive form of evil even than a butcher like Assad. As the blogger Razib Khan argued last week, the would-be caliphate is “utopian in its fundamentals,” and so its ruthless religious cleansing isn’t just a tyrant’s “tool to instill terror” and consolidate power; it’s the point of gaining power, an end unto itself…

But in this case, such a plan is visible. We do not need to re-invade or restabilize Iraq to deal ISIS a blow and help its victims, because Kurdistan is already relatively stable, and the line of conflict is relatively clear. And the Kurds themselves, crucially, are a known quantity with a longstanding relationship to the United States — something that wasn’t on offer in Libya or Syria.

By giving the Kurds breathing room, the president is doing the honorable thing. Throughout America’s decadeslong entanglement in Iraq, it is the Kurds who have been our firmest friends. Right now, Kurds are fighting and dying to protect their homeland, yes, but also to defend Yazidis and Christians who cannot defend themselves. They are fighting for the entire civilized world, and for a country as powerful as our own to not lend them assistance would be genuinely shameful—not least because it is the U.S. invasion of Iraq that has contributed so much to that country’s unraveling.

I am a pessimist. Though I sincerely hope that the limited airstrikes authorized by the president will be enough to force ISIS into retreat, I don’t expect this gruesome war to end tomorrow. We need to start thinking about the Yazidis and the Christians and the other persecuted Iraqis who will need to find shelter somewhere other than Iraq. The United States welcomed as many as 130,000 refugees from South Vietnam after the fall of Saigon in 1975. We might have to welcome just as many from Iraq in the years to come.

U.S. warplanes can work to keep ISIS from advancing into Irbil while avoiding the type of intensive campaign that would be needed to drive them out of their new strongholds, such as the city of Mosul, the heart of the so-called caliphate that ISIS declared in June. In a sense, they are preserving the status quo.

While trying to uproot ISIS in a major city like Mosul would be extremely difficult — and also kill a lot of civilians — strikes like today’s involve hitting the advancing militants in more open terrain.

To stick with Obama’s preference of using sports analogies to explain his foreign policy, the U.S. looks to be playing defense against ISIS, not offense. A broader military effort to defeat ISIS in Iraq and Syria may not be in the cards right now.

Yet this containment policy is arguably what allowed ISIS to gain strength in the first place, initially inside Syria and later in Iraq. Syrian rebels have warned from the outset that allowing the conflict to continue would let extremists take root — an argument that Assad and his backers could make too. As the top Syrian rebel commander at the time warned this reporter in the summer of 2012, when the civil war was escalating: “Leaving Syria like this is very dangerous. It may become another Afghanistan or Iraq.”

Whatever the reasoning, relying solely on humanitarian arguments to justify American action could create problems for the Obama administration down the road. While the trapped Yezidis must be rescued, this is not the only objective that limited U.S. military force can and should achieve. In fact, if initial reports are accurate, the first airstrikes were not against ISIS at Sinjar mountain, which is near Syria, but against targets near Erbil, far to the east, nearer the Iranian border. Such strikes are welcome — Kurdish forces have fought alongside the U.S. in more than one war — but the rationale is more strategic than humanitarian. While Americans are unlikely to protest this distinction today, the White House may open itself up to criticism of overstepping its self-defined mandate if it continues to use limited airpower for strategic gains after the immediate humanitarian crisis is resolved.

Consider some parallels with what happened in Libya two years ago. The U.S. and its allies justified United Nations-sanctioned military intervention solely on humanitarian grounds, but went on to use force to help one side of a civil war prevail over the other. This infuriated Russia, which in part led to the subsequent inability of the UN to take any meaningful action in Syria, given Putin’s vow not to be hoodwinked by the West yet again. No, the U.S. doesn’t need a UN Security Council resolution for action in Iraq, as it is undertaking airstrikes at the behest of the Iraqi government. But overstepping the stated goal may well backfire again — by engendering the resentment of the American people, who may feel that the full case for even limited force was never presented to them. The manner in which Obama made the case for action now may severely limit his options for doing what may be needed in the future.

“I do think the Kurds used that time that was given by our troop sacrifices in Iraq,” Obama added. “They used that time well, and the Kurdish region is functional the way we would like to see. It is tolerant of other sects and other religions in a way that we would like to see elsewhere. So we do think it’s important to make sure that that space is protected, but, more broadly, what I’ve indicated is that I don’t want to be in the business of being the Iraqi air force. I don’t want to get in the business for that matter of being the Kurdish air force, in the absence of a commitment of the people on the ground to get their act together and do what’s necessary politically to start protecting themselves and to push back against ISIL.”…

The president said that what he is telling every faction in Iraq is: “We will be your partners, but we are not going to do it for you. We’re not sending a bunch of U.S. troops back on the ground to keep a lid on things. You’re going to have to show us that you are willing and ready to try and maintain a unified Iraqi government that is based on compromise. That you are willing to continue to build a nonsectarian, functional security force that is answerable to a civilian government. … We do have a strategic interest in pushing back ISIL. We’re not going to let them create some caliphate through Syria and Iraq, but we can only do that if we know that we’ve got partners on the ground who are capable of filling the void. So if we’re going to reach out to Sunni tribes, if we’re going to reach out to local governors and leaders, they’ve got to have some sense that they’re fighting for something.” Otherwise, Obama said, “We can run [ISIL] off for a certain period of time, but as soon as our planes are gone, they’re coming right back in.”

Within hours of U.S. military jets and drones conducting a strike on ISIS artillery that had been used against Kurdish forces defending Irbil, ISIS supporters called for retaliatory attacks against the United States.

“It is a clear message that the war is against Islam and the mujahideen. The mujahideen must strive and seek to execute proactive operations in their own home, America, to discipline America and its criminal soldiers,” Abu al-Ayna al-Khorasani, an administrator of Shumukh al-Islam, the top-tier forum for ISIS propaganda, wrote on his account Friday, according to a translation by the SITE Intelligence group.

Other ISIS supporters railed against the United States using the Twitter handle #AmessagefromISIStoUS, posting images of the wreckage of the twin towers. “Don’t forget 11 Sept .. Maybe US citizens want more like that,” one extremist tweeted.

The United States cannot and should not intervene every time there’s a crisis in the world. But when there’s a situation like the one on this mountain—when countless innocent people are facing a massacre, and when we have the ability to help prevent it—the United States can’t just look away. That’s not who we are. We’re Americans. We act. We lead. And that’s what we’re going to do on that mountain. As one American who wrote to me yesterday said, “it is the right thing to do.”