WASHINGTON (CBSDC) — A former high-ranking CIA official believes it will be difficult for the United States to act to prevent another terror attack.

“The lesson of 9/11 was, can we as a nation act before we get attacked?” former Deputy CIA Director Michael Morell told CBS’ “Face the Nation.” “That is very difficult. President [Franklin] Roosevelt could not bring the American people along to intervene in World War II until we were attacked in Pearl Harbor, so it is very difficult for a president to bring a nation along to say, ‘Let’s act now to disrupt what we know is going to happen.’”

Morell stated the United States needs to shrink the safe haven of the Islamic State of Iraq and Syria.

“We have to put pressure on them in the safe haven and shrink the safe haven. That’s lesson learned number one of defeating al Qaeda in South Asia. Lesson number two is you’ve got to remove the leadership in rapid succession,” the CBS News senior security contributor said, adding that ISIS has “the single most important advantage” in the form of a safe haven in Iraq and Syria.

Morell also said there’s a “frightening” similarity in how today’s terror threats mirrors the pre-9/11 years.

“For me who lived through the pre-9/11 years there’s a similarity here that’s a bit frightening to me,” he explained to “Face the Nation.” “You have a group who says it wants to attack us, just as [Osama] bin Laden said he wanted to attack us, you have them building that capability just as bin Laden built it, we don’t have great visibility into that capability, just as we did not do then.”

He continued, “We just had a major attack overseas, embassy bombings in 1998, Paris now, that should be a wake-up call. The similarities are very concerning.”

The Belgian capital of Brussels has been on lockdown for three consecutive days as officials say a Paris-style attack is imminent. At least 130 people died in the Paris terror attacks.

In an interview with NBC’s “Today,” Secretary of State John Kerry said that people must not succumb to the fear from ISIS.

“People need to not panic. There is a strategy in place growing by the day, and I have no doubt whatsoever that with the help of all the nations that are united against Daesh, they are going to be defeated, and we’re going to do everything in our power to hasten that journey,” Kerry said.

A new CBS News Poll finds that 66 percent of Americans don’t believe President Barack Obama has a clear plan to deal with the terror group.