Israeli and American flags
Israeli and American flagsThinkstock

A Pew Research Center survey conducted in 40 countries has found that Iran's nuclear program is seen by Americans as the #2 global threat – after the threat posed by the Islamic State (ISIS).

Surprisingly, American citizens' concern about both Iran and ISIS is greater than that of Israeli citizens. And yet even as the percentage of Americans expressing concern about Iran is higher, Israelis are the only public surveyed to rate Iran as their top concern among the international issues tested.

According to the survey, 53% of Israelis have substantial concerns about the threat posed by Iran’s nuclear program. Israeli Jews (59%) are far more likely than Israeli Arabs (23%) to express anxiety on the issue.

The survey also shows that Israel is the only country out of the 40 surveyed in which Iran is seen as the top global threat. However, the survey did not include Saudi Arabia and the other Gulf states, which are known to be very concerned about Iran's nuclear ambitions.

Roughly six-in-ten (62%) Americans say they are very concerned about Iran. While a median of 42% of Europeans express strong concern about Iran, according to Pew, only British citizens consider it to be one of the top two global dangers. Relatively few people in Latin America, Africa, Asia and the Middle East say they are very concerned about Iran’s nuclear program.

A majority of Americans (68%) and Canadians (58%) are also very concerned about the Islamic State. In both countries, anxiety about ISIS is the top concern among the issues included in the survey. Concern is similarly high in a number of Asian nations, including South Korea (75%), Japan (72%), Australia (69%) and Indonesia (65%). ISIS is the top concern in all four countries.

The publics in a full 14 countries expressed the greatest concern about ISIS. In Europe, a median of 70% express serious concerns about the threat posed by the growing organization. Trepidation is greatest in Spain (77%), but even in Poland, where only 29% express serious worries, fear of ISIS is second only to worries about tensions between Russia and its neighbors.

As ISIS continues to take over territory in Iraq and Syria and conduct gruesome executions, concern in neighboring countries is high. More than 8 of every 10 Lebanese (84%) are very concerned about ISIS. Among Muslims in Lebanon, Syria’s western neighbor, fear is palpable: 90% of Sunnis and 87% of Shi'ites say they are very concerned, compared with 76% of Christians. More than half in Jordan (62%) and the "Palestinian territories" (54%) also express substantial concern about ISIS.

Worries about the systematic hacking of computer networks are highest in the US (59%) and South Korea (55%), both of which experienced high profile cyberattacks in recent years. 

The global survey was conducted in May among 45,435 people in 40 different countries in all five continents.