Global stability - economic as well as political - is at risk.

Iraq may have been a preview of that, but it's still redeemable if we get out fast. In a war with Iran, we'll get dragged down for 20 or 30 years. The world will condemn us. We will lose our position in the world.

However, if Moscow regains control over Ukraine, with its 52 million people and major resources as well as access to the Black Sea, Russia automatically again regains the wherewithal to become a powerful imperial state, spanning Europe and Asia.

Today it is infinitely easier to kill one million people than to control one million people.

To put it in a terminology that hearkens back to the more brutal age of ancient empires, the three grand imperatives of imperial geo-strategy are to prevent collusion and maintain security dependence among the vassals, to keep tributaries pliant and protected, and to keep the barbarians from coming together.

We didn't push the Russians to intervene, but we knowingly increased the probability that they would.

I think the sheer attrition of American global domination will create circumstances in which the Chinese will be tempted to reach out for more influence, including in regions in which we have special interests, such as the Middle East, from which they already obtain a great deal of their energy. And that region will be seeking some new superpower patron.