Cyberattacks are the most serious threat facing the United States, even more so than terrorism, according to American defense experts.

Almost half of the US national security leaders, or 45.1 percent, who responded to a newly released poll by Defense News -- a specialist publication -- identified cyberwarfare as the principal danger to the country.

Those questioned included leaders in national security policy, the military, congressional staffs and the defense industry.

Terrorism is viewed as the next greatest threat by leaders who identified themselves as Republicans, while climate change was cited by those identifying as Democrats, according to the poll.

More than 350 senior defense leaders responded to the poll in late November, answering two dozen questions across a range of defense issues.

Iran was named as the top threat in the Middle East (54 percent), followed by terrorism (43.3 percent). In Asia, China got a relative majority (47.6 percent), followed by North Korea (28.8 percent).