Story highlights Polls identify a sense of fear in the country around terrorism and terrorists

Videos of beheadings posted to Youtube are displayed on TV and the Internet

Politicians seem willing to exploit the fear to motivate voters

Late Thursday morning, Iraqi Prime Minister Haider al-Abadi told a group of reporters in New York that his country had uncovered a plot by ISIS sympathizers to attack subway systems in Paris and New York. Al-Abadi, who was in New York attending the opening of the United Nations General Assembly, said the information had come from his country's intelligence service.

The Associated Press soon put out a report based on the Iraqi official's comments and the ISIS political/media/security machine shifted into higher gear.

Though federal law enforcement and intelligence agencies quickly cautioned that they could not confirm the Iraqi report, social media exploded with the story. Cable news outlets, including CNN, Fox and MSNBC, led their news hours during the late afternoon with the story. The story was also featured on the evening news broadcasts on NBC and CBS, and a number of news outlets featured it the next morning.

The news organizations stressed that U.S. officials were spreading doubt on the report. Still, often superimposed banners with messages such as "U.S Blindsided By Iraqi Terror Warning," and "Officials: No Hint of ISIS Plot Against Subways" left the viewer unsure what to think.

New York officials, prompted by the report, deployed SWAT teams and K-9 units to the city's subway stations, sent uniformed patrol personnel to check on all 450 stations in the subway system, randomly inspected handbags and luggage and kept officers on duty after their shifts ended. By the next day, heavily armed officers were patrolling subway systems in cities across the country.

All because of a report that had been debunked early on.

Welcome to the Great American Freakout: a time and space where the whole country seems to be infused with, and contributing to, an overriding sense of fear of terrorism in general and ISIS in particular. Despite ISIS not having launched any attacks on U.S. soil and repeated assurances from federal officials that they have not detected evidence of any imminent threats, nearly 60% of respondents in a recent CBS/New York Times poll said they felt ISIS was a "major threat" to the United States.

Indeed, a CNN poll taken in mid-September indicated that 71% of Americans felt ISIS already had operatives working inside the country.

While there is little question that ISIS could pose a threat to the United States if left unchecked, some security experts said they believe the current hysteria is overblown.

"It's hard to imagine a better indication of the ability of elected officials and TV talking heads to spin the public into a panic, with claims that the nation is honeycombed with sleeper cells, that operatives are streaming across the border into Texas or that the group will soon be spraying Ebola virus on mass transit systems — all on the basis of no corroborated information," Daniel Benjamin, a former National Security Council worker who teaches at Dartmouth College, recently told The New York Times.

But the fear is real and it is palpable and its existence says much, not only about the nature of ISIS, but also about the changes in America politics, media and psychology in the last few decades. This is not to say there are no reasons -- real or imagined -- for Americans to be so afraid. In fact there are at least six.

The video: While the ISIS videos did not show the actual slayings of James Foley and Steven Sotloff, they did end with the grisly scene of their decapitated heads lying on their bodies. The impact on the viewing American public was chilling, not just for its barbarity, but also its other worldliness.

JUST WATCHED Growing public fear over terror threat Replay More Videos ... MUST WATCH Growing public fear over terror threat 01:57

JUST WATCHED Sen. doesn't want U.S. leading ISIS fight Replay More Videos ... MUST WATCH Sen. doesn't want U.S. leading ISIS fight 05:10

JUST WATCHED New CNN Poll: The ISIS Impact Replay More Videos ... MUST WATCH New CNN Poll: The ISIS Impact 02:34

"The concept of a beheading is so far out of our normal way of thinking," said Donna Fiedler, an associate professor of social work at LaSalle University who has study how psychological trauma affects individuals. "It's not something we regularly think about or even have in our conceptual maps. So this is something completely new and scary."

It is also intensely personal. Images of most other terror attacks tended not to show individuals who were being killed or about to die. "I think we shouldn't underestimate the power of the particular; the power of the individual, said Roy Peter Clark, a senior scholar at the Poynter Institute. "It's like the little girl in the red dress in 'Schindler's List.' There's death all around her. But you can recognize her as an individual. What that inspires is empathy."

New media/old media: "ISIS has proved to be very adept, very talented ... in ratcheting up the hysteria, ratcheting up the image of their influence far beyond what their actual military capabilities are," former "CBS News" anchor Dan Rather said recently on CNN's "Reliable Sources." Indeed, in producing a steady stream of slickly produced videos that can be downloaded onto smartphones and tablets, ISIS has brought its brutality into the palms of our hands, as well as our living rooms. So whenever someone seeks to play down the threat, evidence supporting it is just a click away.

By giving ISIS saturation coverage, old media has played a role in keeping the public on the edge of its seat with regard to ISIS. In many ways ISIS is an irresistible story for television. ISIS is dramatic. It is mysterious. It is potentially dangerous. It has political ramifications. And it has pictures: the life blood of TV. Battlefield pictures, hostage pictures, scary pictures.

"There's something about the structure of television news that makes small threats big," said Brian Stelter, host of CNN's "Reliable Sources." "It's the graphics and the color and the repetition. Probably the repetition more than anything that makes these guys seem like they're 10 feet tall."

Partisan politics: This week Scott Brown, the Republican candidate for the senate from New Hampshire, unveiled a commercial accusing the Democratic incumbent, Jeanne Shaheen, and President Obama of failing to adequately protect the country against the ISIS threat. "Radical Islamic terrorists are threatening to cause the collapse of our country," Brown intoned on the ad. "President Obama and Sen. Shaheen seem confused about the nature of the threat. Not me."

A Republican operative told CNN's Dana Bash and Deirdre Walsh that polling and focus group data indicates that, in the wake of ISIS' emergence, national security concerns are gaining in importance, especially among married women with children. Appealing to these swing voters and to the party's conservative base, which according to polls has shown the most concern about ISIS' terror, GOP strategists feel is a key to victory in the midterm elections. As a result, variations of the Brown ad may soon start appearing across the country. Whether they succeed or not, there is no doubt they will amp up the fear quotient.

They're everywhere! They're everywhere! To hear some tell it, ISIS is an enormous army with fifth columns operating in big cities all over the country. It is more than a little disconcerting to hear that the estimates for the number of ISIS fighters have jumped dramatically from about 10,000 to as many as 30,000. But some analysts note that the first projection was a year old, and that the marked increase in fighters may be ephemeral. "We have seen that when jihadist groups roll over territory they pick up a lot of riff-raff," said Daniel Benjamin. "A lot of young men join up, mainly to get money to feed themselves every day." So, if ISIS is forced to retreat, many of these new converts may simply melt away.

What is worrying is the number of foreign fighters in the group. The number of foreigners fighting in Syria is estimated to be more than 10,000. That may sound perilous. But the vast majority of them come from places such as Jordan or Tunisia or Saudi Arabia. A few of these, perhaps only a little more than a dozen, are Americans. "There are only about a dozen Americans fighting for ISIS and two of them are already dead," said Peter Bergen, a national security analyst for CNN. "There is no evidence that any of the Americans fighting in Syria have been involved in plotting attacks here at home. So I think this particular threat of ISIS is wildly overstated."

Sure, there are thousands of Europeans, many of them hailing from countries like the United Kingdom and France where visas are not required to travel to the United States. But many are already being tracked by their governments, Bergen said. And to carry out an attack, especially a large-scale one, they would have to travel here, acquire weapons, or produce bomb-making material without arousing suspicion.

Perhaps the most dangerous homegrown problem is individuals who are inspired by ISIS to commit murderous acts, such as Alton Nolen, who allegedly beheaded a co-worker in Moore, Oklahoma. But Nolen, who told police he was "oppressed" at work, could have found inspiration from any group that has committed violent acts and received widespread news coverage. There may not be anything special about ISIS.

JUST WATCHED New ISIS video mocks airstrikes Replay More Videos ... MUST WATCH New ISIS video mocks airstrikes 01:47

JUST WATCHED How did Carney describe ISIS in 2013? Replay More Videos ... MUST WATCH How did Carney describe ISIS in 2013? 06:31

JUST WATCHED CNN Poll: Obama dovish on foreign policy Replay More Videos ... MUST WATCH CNN Poll: Obama dovish on foreign policy 01:22

JUST WATCHED Did intel community warn Obama on ISIS? Replay More Videos ... MUST WATCH Did intel community warn Obama on ISIS? 05:31

Perhaps, most important, a number of experts said, there is little evidence ISIS is interested in anything but establishing a caliphate in the Middle East. Unlike al Qaeda, attacks on America do not seem to be a priority, at least for now. "The key thing is that they are in a fundamentally different business," said Benjamin. "They want to take and hold territory."

Red line fever: Public fear is always heightened when public faith in their leaders to handle pending crises is shaken. Buoyed by his dispatching of Osama bin Laden, public opinion polls gave Obama high -- or at least passably good -- grades for his handling of foreign affairs into the summer of 2013. Then came the issue of Syria's use of chemical weapons. Having drawn what he himself termed a "red line" that the Bashar al Assad regime should not cross with regard to using his chemical weapons, Obama seemed to back away from military action when Damascus crossed it. Even though Syria eventually gave up its chemical weapons, Obama came off in the minds of many as feckless and weak. Public faith in his handling of foreign policy was shaken and has yet to recover. In 2012, a Pew Research Center poll found that 38% felt the President was "not tough enough" in his foreign policy dealings. After the Syria chemical weapons affair, 51% of the public, according to a Pew poll, felt that way. In the latest CNN/ORC International Poll, 51% of the public said they do not trust Obama as commander in chief of the armed forces.

With so little faith in the ability of their leader to protect them, it is not surprising that the level of fear has risen.

9/11, CYA: When the second jet slammed into a World Trade Center tower on September 11, 2001, the whole way the country looked at its vulnerability to terrorism changed. But, as much as the public mood changed, it is the shift in the psyche of politicians and governmental officials that is perhaps most important. Having missed obvious signals that could have alerted them to the pending attacks and being hauled before the 9/11 Commission to have their mistakes publicly aired, the political mindset is now don't dismiss any threat -- no matter how inconsequential. Rather than calming the public anxiety, politicians may inadvertently stoke it.

"We know how to ratchet up," said Juliette Kayyem, a former deputy director of Homeland Security in the Obama administration and now a CNN contributor. "It's harder to ratchet down."

There doesn't seem to be any political price to be paid for overplaying a threat and keeping people on edge. But underplaying one and being wrong could mean the end of a politician's career. "I haven't seen much of a political downside of putting out even a bogus terror threat warning, even if there is only the slightest possibility there is something to it" said Philip Shenon, author of "The Commission: An Uncensored History of the 9/11 Investigation." "Nobody's going to hold you to it."