A day before the Islamic State released a video of the brutal execution of American journalist James Foley, President Obama declared at a White House news conference that defeating the Islamic State was not his responsibility. “We’re not the Iraqi military, we’re not even the Iraqi air force,” Obama said, adding “I am the commander in chief of the United States armed forces, and Iraq is gonna have to ultimately provide for its own security.”

That attitude — that refusal to lead — is precisely why the Islamic State has been able to take control of a swath of the Middle East the size of Belgium and carry out the crimes against humanity we are witnessing today, from burying women and children alive to crucifixions to the beheading of a U.S. citizen.

Even after that horrific act, Obama continued to play down the threat posed by the Islamic State and United States’ responsibility to stop the militants. At a second news conference after the Foley execution, Obama once again dismissed the idea that the United States was at war with the Islamic State. “They may claim out of expediency that they are at war with the United States or the West, but the fact is they terrorize their neighbors,” Obama said.

They do not claim to be at war with the United States. They are at war with the United States. Even Obama’s own deputy national security adviser, Ben Rhodes, admitted that the Foley execution “represents a terrorist attack against our country.” And for the Islamic State, that was only the beginning. It will not be satisfied with killing one U.S. citizen in the deserts of the Middle East. It wants to kill many thousands right here in the United States of America.

Even more disturbing was Obama’s assessment of how the Islamic State will meet its demise. “People like this ultimately fail,” Obama declared passively, “because the future is won by those who build and not destroy.” Sorry, Mr. President, the Islamic State is not going to somehow magically collapse under the weight of its bankrupt ideology. People like this don’t “fail.” They have to be stopped. Nazi Germany didn’t fail. It was defeated. And the Islamic State needs to be defeated — something that will not happen without vigorous U.S. leadership.

Over at the Pentagon, Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, seemed to understand this. “This is an organization that has an apocalyptic end-of-days strategic vision that will eventually have to be defeated,” Dempsey said last week. “Can they be defeated without addressing that part of the organization that resides in Syria? The answer is no.”

Apparently that was too forward-leaning for the Obama White House. On Sunday, Dempsey suddenly and mysteriously reversed himself, telling CBS News “he still believes the insurgent group is still more a regional threat and is not plotting or planning attacks against either the U.S. or Europe.”

But Dempsey was not alone in his original, candid assessment of the danger posed by the Islamic State. Defense Secretary Chuck Hagel went so far as to call the Islamic State “an imminent threat.” Well, if the Islamic State is an “imminent threat” and needs to be “defeated,” what is the holdup in attacking its command, control and communications in Syria? Why isn’t the United States going beyond its current pinprick strikes in Iraq designed to contain the Islamic State, and executing a comprehensive military strategy to defeat the Islamic State?

It appears that the holdup is Obama himself. Instead of leading, Obama is seeking political cover. Administration officials say that if he eventually decides to launch a broader military campaign against the Islamic State, he may request congressional authorization first. Good grief. He does not need new congressional authorization. The Islamic State is an al-Qaeda offshoot. The United States had been engaged in combat with the Islamic State for years. This is the same group the United States defeated during the 2007 Iraq surge — before Obama took our boot off its neck. Obama has all the legal authority he needs to fight and (re-)defeat the Islamic State. He simply needs to use it.

Up until now, Obama has been more concerned with stopping mission creep than stopping the Islamic State. That needs to change. Taking back the Mosul dam was great. But we’ll know Obama is serious when he helps local forces retake Mosul itself — and drives the Islamic State from its havens in Iraq and Syria that it should never have been allowed to take in the first place.

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