Our world is becoming darker. The dangers are increasing from North Korea, whose recent provocation underscored the need to impose a higher price on this rogue regime, a problem that is not just the United States alone, but a problem for us all.

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.

You can overcome wrong technology. Your people have the initiative, they see the problem, no big deal ... you can't overcome bad culture. You've gotta change whoever is in charge.

Congressman [Mike] Pompeo said he believes the intelligence agencies' claims that Russia hacked the US election.

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.

We have the most skillful, firecest, and certainly the most ethical ground forces in the world... I'm not saying we have to commit right now, but certainly don't pull it off the table.

Right now, Russia's future should be wedded to Europe. Why they see NATO as a threat is beyond me. Clearly, NATO is not a threat.