As the economy falters and Russian Prime Minister Vladimir Putin looks vulnerable, he could force President Dimitri Medvedev to resign, change the constitution, and get himself reelected as president. In other words, Russia could become a dictatorship in all but name. And by the way, because of an understanding between Russia and Iran that they will respect the status quo in Central Asia and the Caucasus, Putin will likely reject Obama’s offer of scrapping missile sites in Poland in return for Moscow’s help in taming Iran’s nuclear ambitions. What is Obama’s next move, then? Obama has spent 100 days being nice to the outside world, but what happens when the outside world – Europe, Russia, Iran – does not return the favor?

And I haven’t even mentioned the possibility of an unraveling in Iraq, an Israeli military strike against Iranian nuclear facilities, or another stock market collapse as the economy refuses to recover quickly. Indeed, there are a slew of nasty probabilities lying in wait to define Obama. There could be more incidents between the U.S. and Chinese navies in the Western Pacific; a country in Africa could implode, requiring a massive relief effort, fraught with the specter of nation-building; the collapse of the North Korean regime could precipitate the mother of all humanitarian interventions, as well as the need for cooperation between the American and Chinese armies.