President Barack Obama was right to order humanitarian air drops - and air strikes - to defend refugees in Iraq from an impending genocide threatened by the Islamic State (ISIS or ISIL). On Thursday night he also said the United States would use force to protect Americans in Irbil and Baghdad, where they advise and help the Iraqi government and the Kurdish province of Iraq.

But drawing a fine line, the president declared, "As commander-in-chief, I will not allow the United States to be dragged into fighting another war in Iraq." That made it clear that he has no intention of committing large U.S. combat forces.

The Pentagon announced Friday that U.S. fighter jets and drones had "successfully eliminated" ISIS targets, including artillery weapons that had been used against Kurdish forces.

However, if air power is insufficient to halt the rapid advances of ISIS, what will be the next step?

Events on the ground in Iraq have already made the president remove a condition he set as recently as June 13 on the use of force in Iraq. On that date he issued a warning that he would not be "dragged back into a situation" where Iraq lacks political cohesion and relies on the United States.

At that time, President Obama said: "The United States is not simply going to involve itself in a military action in the absence of a political plan by the Iraqis that gives us some assurance that they're prepared to work together."

That plan has not yet come together, as the president acknowledged in his statement Thursday night, saying, "Iraqi leaders need to come together and forge a new government that represents the legitimate interests of all Iraqis, and that can fight back against the threats like ISIL. Iraqis have named a new president and a new speaker of Parliament, and they are seeking consensus on a new prime minister. This is the progress that needs to continue in order to reverse the momentum of the terrorists who prey on Iraq's divisions."

Limited actions to warn the Islamic State that there are new "red lines" around Irbil and Baghdad, and to give Kurdish and Iraqi forces time to regroup and fend off the ISIS attacks, are nevertheless military actions.

And Mr. Obama has already put Americans in harm's way by sending military advisers to Irbil and Baghdad.

Even the humanitarian assistance to the persecuted Yezidis in their mountainous sanctuary will serve only as a stopgap measure if there is no practical military plan for keeping them out of the clutches of ISIS.

So again, what's next? Will the U.S. be able to restrict its military actions to the current air attack on ISIS? Or will events force more American military action, despite the president's unwillingness to embroil the nation in another war in Iraq?

So far, the U.S. response has obviously been ad hoc, in reaction to events.

At present, the use of air power, as a humanitarian response, is required.

But the Obama administration needs to develop and implement an effective long-term strategy to respond to the chaos in Iraq. And the president must make his intentions - and resolve - clear to not just the American people and our allies but to ISIS.

At this harrowing point, though, the president must do whatever is necessary in the short term to protect Americans still in harm's way in Iraq.

And that includes continued air strikes.