DAVOS, Switzerland — At the recent World Economic Forum meeting of top political, business, intellectual and civil-society leaders, the discussions centered on a range of major international challenges — from new threats to the growing strain on water and other resources.

The discussions brought home the point that at a time of ongoing shifts in economic and political power, greater international divisiveness is making it more difficult to build a consensual approach on the pressing challenges.

Indeed, new fault lines are emerging. The changing global equations are reflected in new realities: the eastward movement of power and influence; the lesser relevance of international structures the United States helped established after World War II; and Asia's rise as the world's main creditor and economic locomotive. While the world is not yet multipolar, it is no longer unipolar, as it had been after the end of the Cold War.