Americans overwhelmingly approve of President Barack Obama’s use of drones to kill foreign terrorists, but fewer support the policy when the target is a U.S. citizen, according to a poll released Tuesday.

Seventy-one percent of Americans back the drone war, which began under President George W. Bush and was expanded under Obama. Only 20 percent oppose the program, according to the CBS News poll. Support is high across party lines — 78 percent of Republicans, 70 percent of Democrats and 68 percent of independents are supportive.

But Americans aren’t as certain about targeting U.S. citizens abroad who have become terrorists. A plurality, 49 percent support the program, and 38 percent oppose killing American terrorists. Fifty-eight percent of GOPers back the idea, along with 48 percent of Democrats and 45 percent of independents.