By: Mark Leon Goldberg on August 07, 2014 For the past two days ethnic Yazidi in Iraq have emptied towns and villages ahead of an unrelenting advance by sunni extremist militants. The ISIS group espouses a hateful, extremist and supremacist ideology. In towns they have captured they have killed civilians based solely on their religion and ethnicity, including Christians and Shia muslims. This second hand account told to George Packer of the New Yorker gives some indication of the threats faced by the Yadizi, not because of anything they have done–but because of who they are. Karim heard that one young man had been executed by ISIS for no reason other than being Yazidi. A friend of Karim’s was hiding in the mountains, running low on supplies, and out of battery power in his phone. Another friend, an Arab (“He is not a religion guy, he’s open-minded, it doesn’t matter if you’re Christian or Yazidi,” Karim said), had stayed in Sinjar and was trapped in his home. Now ISIS was going house to house, with information provided by locals, looking for Iraqi soldiers and police, for people with money, for Kurds. They had already taken away the friend’s brother, a police officer. No one knows for sure how many people ISIS has killed since the attack on Sinjar. Karim heard that it is many hundreds. Now, there are about 40,000 Yazidi who have fled to a mountain in Sinjar, Iraq. They are running out of food and water, but are trapped on all sides by ISIS militants. This has all the potential to be sudden and catastrophic mass atrocity event. The White House said today that President Obama is considering authorizing military force to prevent this slaughter. The administration official said that “the president is weighing both passive and active options,” defining passive action as dropping humanitarian supplies. He added, using an alternative name for ISIS, “More active, we could target the ISIL elements that are besieging the base of the mountain.” If I had to guess, I would think that President Obama will decide to use military force to strike at ISIS targets besieging this civilian population. The precedent here is Libya. You will recall that in February of 2011, Gaddafi’s soldiers had surrounded the city of Benghazi as the Libyan leader broadcast his intention to commit a mass slaughter of the residents therein. President Obama famously “led from behind” to advance a Security Council resolution authorizing strikes against Gadaffi’s forces. Benghazi never fell to Gaddafi. I think it’s fair to say that President Obama is deeply wary of the value and utility of military intervention in most circumstances (see: Syria). But his actions in Libya suggest that he is willing to use American military power to prevent the imminent and sudden mass slaughter of civilians, at least when such intervention comports with international law. In this case, the decision is even easier because the Security Council would not need to approve this intervention for it to be formally legal, as Iraq has requested assistance. So, I would expect that US airpower will be summoned in the very near future to strike at ISIS targets in Iraq. The key question though is how limited will those strikes be? Will they simply target the ISIS forces in Sinjar, or be more of a decisive blow against ISIS elsewhere in Iraq?