So What Will You Do, Mr. President?

Denunciations won’t stop the men who killed James Foley.

President Obama on Wednesday condemned the made-for-YouTube murder of American James Foley with as much passion as we’ve seen from the cool Commander in Chief.

He said that Foley’s killers in the jihadist Islamic State in Iraq and al-Sham, or ISIS, “have rampaged across cities and villages, killing innocent, unarmed civilians in cowardly acts of violence. They abduct women and children, and subject them to torture and rape and slavery. They have murdered Muslims—both Sunni and Shia—by the thousands. They target Christians and religious minorities, driving them from their homes, murdering them when they can for no other reason than they practice a different religion.”

All of this is horribly true. It was also true a year ago. The question now—what the world wants to know now, Mr. President—is what are you going to do about it?

Six years into this Presidency, we know Barack Obama can do empathy. We know he can channel a family’s grief for a murdered son and express a nation’s outrage. What we don’t know is if he can muster the will and fortitude to defeat an enemy that is growing in strength and danger on his watch. This is what America and the world need from a President when killers are on the march.

If it serves any purpose, the butchery of James Foley will open more eyes about the threat ISIS poses to the Middle East and to America. Make no mistake, Foley was killed because he was American. The masked murderer in the video made that clear. Captured in Syria two years ago, the courageous journalist may have been kept alive precisely for this kind of public execution. The video also displayed another captured American freelance journalist, Steven Sotloff, whose fate it said would depend on Mr. Obama’s “next decision” on bombing in Iraq.

It is folly to think this brutality will be confined to unlucky journalists or the sands of western Iraq. ISIS knows which country’s bombs have forced its retreat from the Mosul Dam this week, and it knows American power is the greatest threat to its dreams of a regional caliphate stretching from Lebanon to Kuwait. The jihadists know they are at war against America.

Yet it is not clear that Mr. Obama is willing to admit even now that America is at war against ISIS. American bombs are hitting ISIS Humvees in northern Iraq, but Mr. Obama continues to limit the military mission to preventing genocide against the Yazidi minority and protecting the U.S. consulate in Erbil. This is a defensive containment strategy. It is not a strategy for killing and defeating ISIS.

But Foley is dead and his killers won’t fail on their own. They will not fail because Barack Obama reached out his hand in peace on Inauguration Day. They will not fail because of a progressive vision that mankind has finally in the 21st century reached some higher level of being. Like every evil in human history, ISIS will stop only when it is forced to stop. This means only when enough of its fanatics have been killed.

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