As David Hart and Spencer Nelson of ClearPath write for Utility Dive, American leadership is essential to bend the curve of carbon pollution downward toward zero. A U.S.-powered international initiative to accelerate progress on a technology essential to that push — long-duration energy storage — would demonstrate that leadership. The United States has always preferred voluntary, cooperative, win-win agreements among nations. International R&D collaboration is the quintessential example of such agreements and has, for that reason, been a staple of American diplomacy since World War II. A new innovation challenge on long-duration energy storage is a perfect way to rebuild American leadership, one that leaders from both parties, in the administration as well as Congress, can agree on.