Americans' 2 biggest fears are now ISIS and cyberattacks

The only thing that scares Americans more than foreign attackers is ISIS, a new survey says.

SEE ALSO: Details emerge in slain Texas fitness instructor case

According to a new Pew poll on perceived international threats, 72 percent of Americans view foreign cyber attacks as a major threat. Eighty percent think that of the terrorist group the Islamic State.

The report was broken down by the respondents' political ideologies, and showed that Americans fear hackers consistently across the political spectrum. Though liberal Democrats overwhelmingly fear climate change more than their more conservative counterparts, cyberattacks still come in as their second-rated fear.

Pew first registered Americans' fear of foreign cyberattacks in 2013; that year, 70 percent of respondents agreed it was a major threat -- second only to "Islamic extremist groups like al Qaeda." According to Google Trends, ISIS became a common search in June 2014, when it captured the Iraqi city of Mosul, and spiked that August and September, when the group released videos depicting the murders of American journalists James Foley and Steven Sotloff.

RELATED: See images of Iraq's female soldiers fighting ISIS:

International cyberwarfare is still an obscure topic for most Americans. The best known example is Stuxnet, a worm discovered in 2010, which successfully overrode and damaged motors in an estimated 1,000 Iranian nuclear centrifuges, effectively setting back Iran's nuclear program. While no country ever officially took responsibility, Stuxnet is widely suspected to be a joint creation by the United States and Israel. Though the U.S. is commonly acknowledged as a great cyber power, with devoted military resources like the Department of Defense's powerful U.S. Cyber Command, it's rare that cyberwar is described to the public in tangible terms.

That doesn't stop the U.S. from trying. In April, the Pentagon announced it was engaging in open cyber warfare with ISIS, though it dropped little hints about what that could mean, especially as ISIS has little online infrastructure to target. Deputy Secretary of Defense Robert Work told reporters that "We are dropping cyberbombs," which quickly became a widelymockedphrase.

Despite the prevalence of Americans' fears, a successful, massive, damaging cyberattack on American infrastructure—a theoretical "cyber Pearl Harbor"—has not yet happened, though there have been attempts. In March, the FBIannounced that the hacker group Syrian Electronic Army, loosely affiliated with Syrian President Bashar al Assad's regime, had partially accessed controls at the Bowman Dam in Rye, New York, though the group didn't do any damage. Some argue, however, that huge, data breaches—like the unknown hackers who hacked the U.S. Office of Personnel Management and stole personal information of 21.5 government employees—including CIA agents in the field—can be just as damaging as attacks on infrastructure.

It's possible respondents' answers were influenced by the threat of personal hacks, as well. While Pew's question specified foreign attacks, Americans are also increasingly victimized by hackers who don't reveal their nationality. Hackers stealing personal information to file fraudulent tax returns is sharply on the rise. So is ransomware, in which a hacker remotely encrypts a person's files, and demands a payment to unlock them. While that's a nuisance for individuals, it can be a nightmare for hospitals, which often simply agree to quickly pay to protect patients' safety.

Pew found that Americans' biggest fears varied wildly depending on respondents' political ideologies—liberal Democrats overwhelmingly fear climate change more than their more conservative counterparts, for instance, while conservative Republicans are overwhelmingly more scared of ISIS. Hacking, however, is the one thing both parties and independents can agree on: It's consistently high across the political spectrum.