Editor’s Note: Peter Bergen is CNN’s national security analyst, vice president at New America and a professor of practice at Arizona State University. He is the author of “Manhunt: The Ten-Year Search for bin Laden – From 9/11 to Abbottabad.” Courtney Schuster is a research associate at New America. Watch “The Seventies” episode on terrorism on CNN Thursday at 9 p.m. ET.

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Peter Bergen: We think of the current, post-9/11 era as the heyday of terrorism

In fact, terrorist incidents in the '70s exceeded today's level of activity -- and took a higher toll, he says

CNN  — 

Terrorists’ bombs going off frequently in New York, Washington, Chicago, and Los Angeles. More than a hundred hijackings of airplanes in the States.

These weren’t the acts of ISIS-inspired terrorists in recent times, but of terrorists in America during the 1970s.

Peter Bergen

Many Americans today are clearly convinced they are gravely threatened by terrorists. According to a January 2015 ABC News/Washington Post poll, 76% of Americans are worried about a “major” terrorist attack in the United States.

In fact, the real Golden Age of terrorism in the United States was during the ’70s, not in the post-9/11 world. Consider that terrorism in the United States was then a quite common feature of life: There were literally hundreds of terrorist bombings, shootings and hijackings in States during the 1970s. In the 14 years since 9/11 there have been by contrast only some two-dozen terrorist attacks in the United States perpetrated by a mix of jihadist terrorists, neo-Nazis, violent racists and anti-government militants, according to a count by New America.

During the decade of the 1970s terrorists killed 184 people in the States and injured more than 600 others. In the decade and a half since 9/11, terrorists have, by contrast, killed 74.

Between 1970 and 1979 nationalist and ethnic terrorists, religious zealots, and anti-war militants frequently attacked American targets. Terrorist attacks typically consisted of bombings of civilian targets in New York, Los Angeles, and Washington that were also interspersed with shooting sprees aimed at the police.

The Weather Underground, an anti-war organization that targeted the Pentagon, the U.S. Capitol and banks, claimed credit for 25 bombings in 1975 alone but could have been responsible for upward of 45, according to the University of Maryland’s Global Terrorism Database.

Other anti-war activists carried out major bombings at Fresno State College, the University of Wisconsin-Madison, and City Hall in Portland, Oregon.

On February 4, 1974, 19-year-old publishing heiress Patty Hearst was kidnapped in Berkeley, California, by the leftist revolutionary terrorist group the Symbionese Liberation Army, which demanded a vast ransom. In a famous case of Stockholm Syndrome, Hearst would later join the Symbionese Liberation Army, emerging with a new revolutionary persona as “Tania.” Despite her claim of brainwashing, Hearst was convicted of bank robbery; after two years in jail her sentence was commuted by Jimmy Carter and she was eventually pardoned by Bill Clinton.

The United States also saw a wave of religious terrorism during the 1970s. The Jewish Defense League, a right-wing religious organization, launched 44 bombings and assaults during the decade, half of which targeted perceived anti-Semitic targets in New York, Los Angeles and Chicago.

During the decade, ethnic and nationalist terrorist groups were frequent perpetrators of violent attacks in the States. The Black Panthers carried out 24 bombings, assaults and hijackings.

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Fuerzas Armadas de Liberacion Nacional, a Puerto Rican separatist group, was responsible for 82 bombings, mostly in New York and Chicago and almost all of which targeted civilians.

The U.S. Department of Transportation found that between 1970 and 1979 there were 112 domestic plane hijackings. While those numbers didn’t differentiate between simple criminal hijackings and those committed for political purposes, hijackings were quite common during the 1970s, but since then they have virtually disappeared.

A watershed moment for American aviation security was the November 10, 1972, hijacking of a Southern Airways flight in Birmingham, Alabama, with 34 people on board. Three hijackers demanded $10 million or they would crash the plane into the nuclear reactors at Oak Ridge, Tennessee. For 30 hours, the three hijackers forced the plane to travel to Cleveland, Detroit, Lexington, Kentucky, Toronto, and ultimately to Havana, Cuba, where the hijackers were arrested by Cuban authorities.

As a result of this incident, the Federal Aviation Administration ordered in December 1972 that within a month all passengers be screened with metal detectors, all carry-on luggage be inspected, and armed guards be posted at boarding checkpoints.

Three years later, LaGuardia airport was targeted by terrorists. Investigators believe 25 sticks of dynamite were placed inside a locker near the TWA baggage claim, blasting shrapnel across the area, killing 11 and injuring 75.

At the time of the explosion, passengers from two incoming flights happened to have already cleared the area, leaving mostly airport employees as the victims. Although the bombing was never solved, Croatian nationalists – who were responsible for three hijackings in the States in the ’70s – were the suspected culprits.

The West writ large did not fare much better from terrorism than the United States during the 1970s. Terrorists in Europe frequently attacked embassies, trains, airports and cafes and an entire OPEC meeting was taken hostage (including 11 oil ministers) in Vienna, Austria. That incident ended after the plane provided to the terrorists landed in Algiers and the 63 hostages were released and their leader, Carlos the Jackal, escaped.

Most infamously, Palestinian terrorists kidnapped and killed a group of Israeli athletes at the 1972 Munich Olympics, an event that was covered live by most of the world’s TV networks that were gathered in Munich to cover the games.

Why were the 1970s the Golden Age of terror? A number of factors were influential: Opposition to the Vietnam War spawned violent leftist groups such as the Weather Underground. In the heady political atmosphere of the late ’60s other violent revolutionary groups also arose, such as the Black Panthers. During this period Palestinian terrorist groups started for the first time operating in the West led most notoriously by Carlos the Jackal who was the Osama bin Laden of his day.

During the ’70s there were also scant government resources directed at the terrorism threat. The first Joint Terrorism Task Force in the States was established in 1980 in New York, which was the first interagency law enforcement group specifically founded to investigate acts of terrorism.

Post-9/11 the United States became, for obvious reasons, a much less congenial environment for terrorist to operate in. On 9/11 there were 35 Joint Terrorism Task Forces. Today there are 104. On 9/11 there were 16 suspected terrorists on the “no fly” list; now there are 40,000. On 9/11 there was no Transportation Security Administration, no Department of Homeland Security and no National Counterterrorism Center, which brings together analysts from across the U.S. intelligence community to analyze terrorism threats and trends.

All these new measures and government agencies make the United States a much harder target for terrorists.

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