Cheney: Order to Shoot Down Hijacked 9/11 Planes 'Necessary'

Former Vice President Dick Cheney on Sunday defended his Sept. 11, 2001, order to shoot down hijacked planes over Washington, saying the call was "necessary."

Cheney gave the authority under the assumption that planes were heading for the nation's capital after hitting the World Trade Center towers in New York City.

The orders were apparently never passed on to fighter pilots -- and came too late anyway, since the hijacked planes had already crashed.

But Cheney defended the call on principle.

"Frankly, I didn't pause to think about it very much," Cheney said on "Fox News Sunday." "Once one of those aircraft was hijacked, it was a weapon. ... I saw it as part of my responsibility."