It's decision time now for Obama on ISIS

Rep. King: ISIS could attack at any time
Rep. King: ISIS could attack at any time   

Although they disagree on exactly what President Barack Obama should say in his prime-time address on Wednesday, experts say he needs to lay out a decisive course of action to reassure American allies and worry the Islamic State.

The president will take the podium less than two weeks after he told the American people that "we don't have a strategy yet" to address the Islamic State (also known as ISIS or ISIL) combatants in Iraq.

And while the president is expected to discuss increasing targeted airstrikes, assisting regional forces, gathering allied coalitions and even perhaps addressing the extremists' operations in Syria, experts tell CNBC that the most important part of Wednesday's speech will be simply proving that the U.S. has a plan.

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President Barack Obama
Yunus Kaymaz | Anadolu Agency | Getty Images
President Barack Obama

"He needs to act as a leader: He needs to be decisive, not contemplative and academic," said Anthony Cordesman, the Arleigh A. Burke Chair in Strategy at the Center for Strategic and International Studies. "He needs to reassure our allies, and to some extent our enemies, that the United States is committed and is taking concrete steps. What we don't need is another speech about the need for caution."

Those caution-focused speeches have been the norm for Obama since ISIS began making headlines in Iraq, as the president at first played down the threat, and then eventually authorized limited U.S. airstrikes to protect American personnel and offer limited assistance to allies on the ground. By last week, Obama signaled a change in outlook at a NATO summit when he said the militants had "significant capabilities," and emphasized taking the fight to ISIS.

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Wednesday's speech is widely expected to be a continuation of that outlook, and may offer the president an opportunity to outline more concrete goals.

"Obama should lay out what his strategic objectives are and identify the resources he's willing to make available to achieve that objective," said Rick Brennan, a senior political scientist at RAND Corp. and a former senior civilian advisor to the U.S. military in Iraq.

Obama's evolving ISIS strategy
Obama's evolving ISIS strategy   

Specifically, Brennan said, if Obama commits to enhancing the capabilities of Iraqi and Kurdish forces, he needs to explain—at least in broad strokes—what he is going to use to realize that goal. More equipment will be minimally useful to these forces without American forces to help train them, Brennan said, so "all we have is words that are not going to be able to be achieved" if the president will not send more military personnel to the region.

Still, experts caution, there is little domestic or international benefit for Obama to explicitly say what the U.S. will not do.

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"Obama should not say what's not going to be employed," said Michael Rubin, a senior lecturer at the Naval Postgraduate School and author of the book "Dancing with the Devil: The Perils of Engaging Rogue Regimes."

"Privately he may want to keep options off the table, but in public he shouldn't say that," Rubin said, explaining that there are strategic benefits to having ISIS leaders worrying that there could be American troops deployed in Syria.

Obama to address nation
Obama to address nation   

'Boots on the ground'

Despite repeated—and ill-advised, according to experts interview by CNBC—assurances that he would not be putting American troops into combat roles in Iraq, Obama has likely already deployed special forces to act against ISIS, Cordesman said. Additionally, the 1,100 military personnel that the president has publicly sent to Iraq to secure U.S. diplomatic facilities and staff are likely engaged in more offensive-minded roles than announced, he said.

But these numbers may not be nearly sufficient to accomplish Obama's stated goal of degrading and ultimately destroying ISIS, according to Brennan, who called the current deployment "a drop in the bucket" compared with what is needed.

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Now, the United States would need about 5,000 to 7,000 troops on the ground for an extended period of time to advise, train and assist the Iraqi and Kurdish forces sufficiently in the fight against ISIS, Brennan said.

"We need to get beyond the point of not thinking about putting American boots on the ground," he said. "In the long run that'll be insufficient to realizing the objectives [Obama] has established for himself."

Rubin, however, said he did not necessarily see the benefits of sending in more American ground troops, as that strategy often leads to "mission creep." Instead, he suggested that American military leaders look to the recapture of the Mosul Dam as a strategic model: American air power provided a "qualitative military edge" that allowed the regional forces to beat back ISIS.

The Syria problem

Several reports ahead of Obama's Wednesday night address have indicated that the president plans to announce airstrikes against ISIS in Syria as part of his plan to take the fight to the militant group. But U.S. action in Syria is a much more complicated task than simply a few targeted strikes, experts warn, and the president's strategy will need to address several concerns.

Still, foreign policy specialists told CNBC that Obama will have to announce plans for Syria on Wednesday night if he has any chance of success against ISIS.

"If we try to divide Syria from Iraq, we will lose," said Danielle Pletka, senior vice president for foreign and defense policy studies at the American Enterprise Institute. "The problem is that [Obama] has had multiple opportunities to do something, and he hasn't."

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As much of ISIS' main bases, leadership and strategic assets are located in Syria, a comprehensive American strategy to destroy the group will be forced to take the battle into that region. But finding appropriate allies on the ground will be difficult, as moderate forces are either indiscernible or weak.

Although the United States does not "have the vetting ability to determine who is moderate and who is not," Rubin said the American military should be looking to the Kurdish forces in Syria for support against ISIS in the region.

Ultimately the best strategy may be to establish U.S. operations in Iraq from which to identify and reach Syrian targets, just as the U.S. does in Pakistan from its Afghanistan bases, Brennan said.

ISIS a localized threat right now: Gen. Clark
ISIS a localized threat right now: Gen. Clark   

Allies and coalitions

The other major question that Obama will have to answer on Wednesday, experts said, is how the U.S. will work with its allies to achieve its goals against ISIS.

A successful U.S. strategy will require actively seeking the support of European and Middle Eastern countries to bolster efforts in Syria, but Obama should avoid becoming beholden to a coalition. His Wednesday address would benefit from "naming the partners he would like in a way that doesn't bind the U.S. to waiting for them," Cordesman said.

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Some U.S. allies may even need to be told—outside of a public speech—not to actively support Islamic State interests, Rubin said. The militant group is estimated to make roughly $3.5 million each day in oil shipments that are presumed to pass across Turkish and Jordanian borders, so "there needs to be a no-holds-barred discussion" with those countries about their role, Rubin said.

As for Obama's Wednesday speech, the president may address "the importance of being on board" with a U.S. strategy, Rubin suggested.

"Enduring commitment"

Although it is not an immediate strategic interest, foreign policy experts told CNBC that Obama should explicitly address the inherently protracted nature of a fight against ISIS in his address.

Calling America's ties to the region an "enduring commitment," Cordesman said he would be watching to see if the president admits "that this isn't going to be something that is so quick and easy that it's not a major problem."

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In fact, Rubin stressed that Obama should not even mention the topics of a victory or a timetable. Estimates of when American forces would cease engagement can put artificial pressures on a mission, and ultimately harm confidence from our allies, he explained.

"What people want to know is what the man seeks to achieve, and not what the limits are in what he seeks to achieve," Pletka said.

—By CNBC's Everett Rosenfeld