LAS VEGAS - OCTOBER 20: The new mall at CityCenter on Las Vegas Boulevard is viewed on October 20, 2010 in Las Vegas, Nevada. Nevada once had among the lowest unemployment rates in the United States at 3.8 percent but has since fallen on difficult times. Las Vegas, the gaming capital of America, has been especially hard hit with unemployment currently at 14.7 percent and the highest foreclosure rate in the nation. Among the sparkling hotels and casinos downtown are dozens of dormant construction projects and hotels offering rock bottom rates. As the rest of the country slowly begins to see some economic progress, Las Vegas is still in the midst of the economic downturn. (Photo by Spencer Platt/Getty Images) File photo of a mall. (credit: pencer Platt/Getty Images)

WASHINGTON (CBSDC/AP) — The former deputy director of the CIA fears that the Islamic State of Iraq and Syria could carry out attacks in the United States.

CBS News national security analyst Mike Morell told “CBS This Morning” Thursday that this terror group poses both short- and long-term threats to the U.S.

“The short-term concern is the Americans that have gone to fight with ISIS and the west Europeans that have gone to fight with ISIS could be trained and directed by ISIS to come to the United States to conduct small-scale attacks,” Morell stated. “If an ISIS member showed up at a mall in the United States tomorrow with an AK-47 and killed a number of Americans, I would not be surprised.”

Morell warned that over the long-term the extremist group could be planning for a 9/11-style attack that killed thousands of Americans.

“Over the long-term I worry that this group could present a 9/11-style threat. It took al Qaeda two-and-a-half years to plan 9/11. It would not surprise me to know that ISIS maybe thinking about going in that kind of direction,” Morell told CBS News.

The United States launched a new barrage of airstrikes Wednesday against the Islamic State extremist group that beheaded American journalist James Foley and that has seized a swath of territory across Iraq and Syria. President Barack Obama vowed relentless pursuit of the terrorists and the White House revealed that the U.S. had launched a secret rescue mission inside Syria earlier this summer that failed to rescue Foley and other Americans still being held hostage.

In brief but forceful remarks, Obama said the U.S. would “do what we must to protect our people,” but he stopped short of promising to follow the Islamic State in its safe haven within Syria, where officials said Foley had been killed. Later, though, the administration revealed that several dozen special operations troops had been on the ground in Syria briefly in an effort to rescue the hostages, but did not find them.

Morell explained that the U.S. needs to start taking territory away from ISIS in an effort to put a dent into the terror organization.

“One requires taking territory away from them so they cannot use it as a safe haven to train. That requires airstrikes and that requires enabling the Iraqi military to do its job,” Morell told CBS News. “The other thing it requires is to take the leadership of ISIS off the battlefield. That means capturing or killing them.”

Western nations agreed to speed help to combat the militants — most notably Germany, which bucked public opposition by announcing it would arm Iraqi Kurdish fighters to battle the Islamic State. French Foreign Minister Laurent Fabius said he was outraged by the beheading, deeming it evidence of a “caliphate of barbarism.” Italy’s defense minister said the country hopes to contribute machine guns, ammunition and anti-tank rockets.

The Islamic State called Foley’s death a revenge killing for U.S. airstrikes against militants in Iraq, and said other hostages would be slain if the attacks continued. Undeterred, the U.S. conducted 14 additional strikes after a video of the beheading surfaced, bringing to 84 the number of airstrikes since they began on Aug. 8.

Two U.S. officials said additional American troops — probably less than 300 — could be headed to Iraq to provide extra security around Baghdad, where the U.S. Embassy is located. That would bring the total number of American forces in Iraq to well over 1,000, although officials said no final decision had been made. The officials spoke on condition of anonymity because they were not authorized to discuss the matter by name.

For much of the past year, and until this summer, the Obama administration was deeply divided on how much of a threat the Islamic State posed to Americans or even other nations beyond Iraq and Syria. But since the militants’ march across northern Iraq in June, and as its ranks swelled almost threefold to an estimated 15,000 fighters, Obama has acknowledged that the Islamic State could become a direct threat to Americans.

Morell told CBS News that the administration might not understand the serious threat ISIS poses.

“In order to make a decision, to take out the leadership of a group … the president has to make a determination the group poses a direct and imminent threat to the United States and that you can’t capture these guys. So the only choice left is to kill them,” Morell said. “”I don’t know if they have made that determination or not,”

The secret mission to rescue the U.S. hostages involved several dozen special operations forces dropped by aircraft into Syria. The hostages weren’t found at an oil refinery, but special forces engaged in a firefight with Islamic State militants before departing, according to administration officials. Several militants were killed, and one American sustained minor injuries.

“The U.S. government had what we believed was sufficient intelligence, and when the opportunity presented itself, the president authorized the Department of Defense to move aggressively to recover our citizens,” Lisa Monaco, Obama’s top counterterrorism adviser, said in a statement. “Unfortunately, that mission was ultimately not successful because the hostages were not present.”

Morell says that with the information coming out about the mission, ISIS will better protect itself against U.S. military undertakings.

“There was a reason the White House wanted to keep this secret and it was a good reason. When we showed up at that oil refinery, the hostages weren’t there. So ISIS was not sure why we came. Now they know. Now they know that we may make an attempt to go after hostages so they will better protect them. And every little detail that is leaked out about this operation gives ISIS information that will help them protect against future operations,” Morell told CBS News.

Jordan and Saudi Arabia, both of whom share a border with Iraq, have dispatched troops to the frontier in a bid to prevent any attempt by the extremists to attack. Iran, an ally of the Shiite-led government in Baghdad, has sent military advisers to help organize Shiite militias in Iraq and defend holy sites.

Foley, a 40-year-old journalist from Rochester, New Hampshire, was no stranger to war zone reporting. He went missing in northern Syria in November 2012 while freelancing for Agence France-Presse and the Boston-based news organization GlobalPost. The car he was riding in was stopped by four militants in a contested battle zone that both Sunni rebel fighters and government forces were trying to control. He had not been heard from since.

He was one of at least four Americans still being held in Syria — three of whom officials said were kidnapped by the Islamic State. The fourth, freelance journalist Austin Tice, disappeared in Syria in August 2012 and is believed to be in the custody of government forces in Syria.

The Islamic State video of Foley’s beheading also showed another of the missing American journalists, Steven Sotloff, and warned he would be the next killed if U.S. airstrikes continued. U.S. officials believe the video was made days before its Tuesday release, perhaps last weekend, and have grown increasingly worried about Sotloff’s fate.

Obama avoided specific mention of the other American hostages in Syria, and was vague on whether the U.S. would significantly ramp up its assault on the Islamic State beyond the airstrikes and small potential increase in troops in Iraq. A third senior U.S. official said the administration was well aware of the risks to the hostages once the strikes began, and would now consider as aggressive a policy as possible to obliterate the militants.

At the State Department, spokeswoman Marie Harf did not rule out military operations in Syria to bring those responsible to justice, saying the U.S. “reserves the right to hold people accountable when they harm Americans.”

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