MEXICO CITY — Shortly before America's elections last November, then Democratic vice presidential candidate Joseph Biden was widely criticized for predicting that an Obama administration would almost certainly be tested by what he called a "generated" international crisis, in much the way that the Soviet Union "tested" U.S. President John F. Kennedy shortly after he assumed office. Biden did not point to a specific region of the world, but mentioned the Middle East, the Indian subcontinent and Russia as the likeliest sources of trouble for the new president.

Impolitic or not, Biden's anxieties seem to have informed several of the administration's early foreign policy decisions. These include Biden's own extension of an olive branch to Russia at last month's Munich Security Conference, and U.S. President Barack Obama's appointment of Richard Holbrooke as special envoy for Pakistan and Afghanistan, and of George Mitchell to a similar post for the Israeli-Palestinian conflict.

But, as pressing as the Middle East, South Asia, and Russia (as well as Iran and North Korea) are, another crisis far closer to home could create as much peril as a nuclear-armed Iran, an aggressively resurgent Russia or even an Islamist-dominated Pakistan.