A country that armed Stalin to defeat Hitler can certainly work alongside enemies of al-Qaida to defeat al-Qaida.

We do not draw red lines unless we intend to carry them out. We have made very clear that we are willing to work with China, and we believe China has tried to be helpful.

What concerned me was that [James Mattis] played not only a critical role as a battlefield commander in Fallujah, but also, afterwards, when he was promoted to various other higher-ranking positions, he served as a convening authority in court-martial proceedings against various marines who had been accused of atrocities - for example, in the Haditha massacre, where a group of marines went on a killing spree after one in their unit was killed.

When you're in operations, the best thing you can do at the top level is get the strategy right. You have to get the big ideas right, you have to determine what is the policy, what is the level of effort you're willing to commit to it? And then you delegate to those who have to execute that strategy to the appropriate level. What's the appropriate level? It's the level where people are trained and equipped to take decisions so we move swiftly against the enemy.

An untrained or uneducated Marine ... deployed to the combat zone is a bigger threat to mission accomplishment ... than the enemy.

I would consider the principal threats to start with Russia, and it would certainly include any nations that are looking to intimidate nations around their periphery, regional nations nearby them, whether it be with weapons of mass destruction or, I would call it, unusual, unorthodox means of intimidating them, that sort of thing.

We face now an era where we're going to be fighting the terrorist threat. I mean, that's simply a reality we are going to have to address that one.