U.S. space exploration inspired a generation of students and innovators, but NASA’s role has diminished, and the number of global space competitors is growing.

Turkey’s geography and membership in NATO have long given the country an influential voice in foreign policy, but the assertive policies of President Erdogan have complicated its role.

With economic inequality at an all-time high, some U.S. presidential candidates are proposing dramatic shifts to the U.S. tax code. How have similar plans worked elsewhere in the world?