The destruction that we have wreaked in the various theaters in which we've been engaged is really quite astonishing. But again, lethality, destruction, killing doesn't seem to achieve our objectives. So, my own sense is that a lack of lethality does not define the core problem.

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.

I think, broadly speaking, the US military's role - US military activism in various parts of the Islamic world over the past several decades has been counterproductive.

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.

We are going to have to continue to keep the pressure on the enemy. There is no room for complacency on this.

In this age, I don't care how tactically or operationally brilliant you are, if you cannot create harmony - even vicious harmony - on the battlefield based on trust across service lines, across coalition and national lines, and across civilian/military lines, you need to go home, because your leadership is obsolete. We have got to have officers who can create harmony across all those lines.

I would happily storm hell in the company of these troops ... how strongly they have demonstrated to the world that free men and women can fight like the dickens.