In a victory for diplomacy, world leaders announced early Sunday that a deal had been struck with Iran over its disputed nuclear program. In what U.S. President Barack Obama called an "important first step" toward addressing the world's concerns over Iran’s motivations and actions and opening a path out of a three-decade long standoff, the deal will curb Tehran’s nuclear ambitions away from a bomb and toward a civilian capability, in exchange for limited relief—for now—from strict sanctions that have devastated the Iranian economy.