New ideas are rare in international politics. The actions of countries on the world stage often seem like endless replays of ancient laws on power and conflict that are impervious to fresh insights and initiatives. And nowhere is the lack of new thinking more acute than in the realm of international institutions, where a set of multilateral organizations established in the wake of World War II still dominates.

Today, however, a big new idea for a new international institution has bubbled to the surface. It is the idea that the next U.S. president should seek to establish a “League of Democracies” (or “Concert of Democracies,” as it is sometimes called). The league would be a free-standing organization separate from—and perhaps one day even replacing—the United Nations.