Extremist groups still believed to be top threat to U.S.

	Major Threat	Minor Threat	Not A Threat	Don't Know
Extremist Islamic Groups	71	19	6	4
ISIS	67	21	5	7
Iran's Nuclear Program	59	28	9	4
Tension Between Russia and Neighbors	53	35	8	4
China's Emergence as World Power	48	33	14	5
Climate Change	48	30	20	2

% of respondents