The man who headed the NSA and CIA under President George W. Bush suggested Friday that mercenaries were needed to deal with growing cyber threats.

Gen. Michael Hayden told the Aspen Security Forum that in the near future, the Department of Defense may have to allow the creation of a "digital Blackwater."

Private sector offense "might be one of those big new ideas in terms of how we have to conduct ourselves in this new cyber domain," Hayden explained. "You think back long enough in history and there are times when the private sector was responsible for its own defense."

"We may come to a point where defense is more actively and aggressively defined even for the private sector and what is permitted there is something that we would never let the private sector do in physical space... Let me really throw out a bumper sticker for you. How about a digital Blackwater?" he suggested.

"I mean, we have privatized certain defense activities even in physical space and now you've got a new domain in which we don't have any paths trampled down in the forest in terms of what it is we expect the government or will allow the government to do. In the past when that has happened, private sector expands to fill the empty space. I'm not quite an advocate for that, but these are the kinds of things that are going to be put into play here very, very soon."

Watch the entire Aspen Security Forum on cyber security here.