In my estimation, there has not been in American history a more important leak than Edward Snowden's release of NSA material – and that definitely includes the Pentagon Papers 40 years ago.

We need the courage to face the truth about what we are doing in the world and act responsibly to change it.

I agree that there are things that should be kept secret.

It's naive and even irresponsible for a grownup today to get her or his information about foreign policy and war and peace exclusively from the administration in power. It's essential to have other sources of information, to check those against one's own common sense, and to form your own judgment as to whether we ought to go to or persist in war.

The effect of that is to poison the flow of information to the President himself and to create a situation where a President can be almost, to use a metaphor, psychotically divorced from the realities in which he is acting.

Those of us who finally saw through the Vietnam war saw through this war, and all the actions that were necessary to end the Vietnam war will be necessary here. I think the American people will get us out of this war.

But it is important always to keep in mind that the danger of harming humans is not connected only or even mainly with telling secrets, there can be great danger in keeping secrets.