This year’s UN summit offers a rare chance for reform of the world’s leading peace and security body but is bedeviled by major power tensions over intractable wars.

The two-year-old war in Ukraine—which is far from deadlocked—could pivot dramatically in the coming months. U.S. decisions will play a decisive role.

South Korea must capitalize on its diplomatic push to bridge the divide between its longtime ally and its combative neighbor.

North Korea’s test of an intercontinental ballistic missile during the week of the Hamburg summit injects an air of crisis into an already tricky set of meetings.