I suddenly realized at the CIA that I had to make life-and-death decisions about people.

An aggressor nation or extremist group could gain control of critical switches and derail passenger trains, or trains loaded with lethal chemicals.

The consequence could be that we would have an escalation that would take place that would not only involve many lives, but I think it could consume the Middle East in a confrontation and a conflict that we would regret.

The reason we've always had a civilian in that job [Secretary of Defence] is because we really believe that it is policymakers who ought to control the military and not have the military control the military.

Companies should be able to share specific threat information with the government without the prospect of lawsuits hanging over their head.

My impression is that Putin feels that he can basically manipulate the West to do what he ultimately wants to achieve, and that he feels he's gotten away with it so far, and that all he has to do is basically play the same game.

I want to reassert again the position of the United States that with regards to Iran, we will not allow Iran to develop a nuclear weapon, period. We will not allow them to develop a nuclear weapon, and we will exert all options in the effort to ensure that that does not happen...The United States stands firmly with Israel, and we have a rock solid commitment to the security of Israel and to the security of its citizens.