Some pundits are surprised that I support destroying the Islamic State in Iraq and Greater Syria (ISIS) militarily. They shouldn’t be. I’ve said since I began public life that I am not an isolationist, nor am I an interventionist. I look at the world, and consider war, realistically and constitutionally.

I still see war as the last resort. But I agree with Reagan’s idea that no country should mistake U.S. reluctance for war for a lack of resolve.

As Commander-in-Chief, I would not allow our enemies to kill our citizens or our ambassadors. “Peace through Strength” only works if you have and show strength.

Our recent foreign policy has allowed radical jihadists to proliferate. Today, there are more terrorists groups than there were before 9/11, most notably ISIS. After all the sacrifice in Afghanistan and Iraq, why do we find ourselves in a more dangerous world?

And why, after six years, does President Obama lack a strategy to deal with threats like ISIS?

This administration’s dereliction of duty has both sins of action and inaction, which is what happens when you are flailing around wildly, without careful strategic thinking.

And while my predisposition is to less intervention, I do support intervention when our vital interests are threatened.

If I had been in President Obama’s shoes, I would have acted more decisively and strongly against ISIS. I would have called Congress back into session—even during recess.

This is what President Obama should have done. He should have been prepared with a strategic vision, a plan for victory and extricating ourselves. He should have asked for authorization for military action and would have, no doubt, received it.

Once we have decided that we have an enemy that requires destruction, we must have a comprehensive strategy—a realistic policy applying military power and skillful diplomacy to protect our national interests.

The immediate challenge is to define the national interest to determine the form of intervention we might pursue. I was repeatedly asked if I supported airstrikes. I do—if it makes sense as part of a larger strategy.

There’s no point in taking military action just for the sake of it, something Washington leaders can’t seem to understand. America has an interest in protecting more than 5,000 personnel serving at the largest American embassy in the world in northern Iraq. I am also persuaded by the plight of massacred Christians and Muslim minorities.

The long-term challenge is debilitating and ultimately eradicating a strong and growing ISIS, whose growth poses a significant terrorist threat to U.S. allies and enemies in the region, Europe, and our homeland.

The military means to achieve these goals include airstrikes against ISIS targets in Iraq and Syria. Such airstrikes are the best way to suppress ISIS’s operational strength and allow allies such as the Kurds to regain a military advantage.

We should arm and aid capable and allied Kurdish fighters whose territory includes areas now under siege by the ISIS.

Since Syrian jihadists are also a threat to Israel, we should help reinforce Israel’s Iron Dome protection against missiles.

We must also secure our own borders and immigration policy from ISIS infiltration. Our border is porous, and the administration, rather than acting to protect it, instead ponders unconstitutional executive action, legalizing millions of illegal immigrants.

Our immigration system, especially the administration of student visas, requires a full-scale examination. Recently, it was estimated that as many as 6,000 possibly dangerous foreign students are unaccounted for. This is inexcusable over a decade after we were attacked on 9/11 by hijackers including one Saudi student who overstayed his student visa.

We should revoke passports from any Americans or dual citizens who are fighting with ISIS.

Important to the long-term stability in the region is the reengagement diplomatically with allies in the region and in Europe to recognize the shared nature of the threat of Radical Islam and the growing influence of jihadists. That is what will make this a comprehensive strategy.

ISIS is a global threat; we should treat it accordingly and build a coalition of nations who are also threatened by the rise of the Islamic State. Important partners such as Turkey, a NATO ally, Israel, and Jordan face an immediate threat, and unchecked growth endangers Kuwait, Saudi Arabia, Gulf countries such as Qatar, and even Europe. Several potential partners—notably, the Turks, Qataris, and Saudis—have been reckless in their financial support of ISIS, which must cease immediately.

This is one set of principles. Any strategy, though, should be presented to the American people through Congress. If war is necessary, we should act as a nation. We should do so properly and constitutionally and with a real strategy and a plan for both victory and exit.

To develop a realistic strategy, we need to understand why the threat of ISIS exists. Jihadist Islam is festering in the region. But in order for it to grow, prosper, and conquer, it needs chaos.

Three years after President Obama waged war in Libya without Congressional approval, Libya is a sanctuary and safe haven for training and arms for terrorists from Northern Africa to Syria. Our deserted Embassy in Tripoli is controlled by militants. Jihadists today swim in our embassy pool.

Syria, likewise, has become a jihadist wonderland. In Syria, Obama’s plan just one year ago—and apparently Secretary of State Hillary Clinton’s desire—was to aid rebels against Assad, despite the fact that many of these groups are al-Qaeda- and ISIS-affiliated. Until we acknowledge that arming the Islamic rebels in Syria allowed ISIS a safe haven, no amount of military might will extricate us from a flawed foreign policy.

Unfortunately, Obama’s decisions—from disengaging diplomatically in Iraq and the region and fomenting chaos in Libya and Syria—leave few good options. A more realistic and effective foreign policy would protect the vital interests of the nation without the unrealistic notion of nation-building.

Paul is the junior U.S. Senator for Kentucky.

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