Glossary
Plain-language definitions for terms you'll encounter in geopolitics and international economics.
Article 5 (NATO)
The collective-defense clause of the North Atlantic Treaty: an armed attack against one ally is considered an attack against all. Invoked once in NATO's history, after the September 11, 2001 attacks on the United States.
Strategic ambiguity
A deliberate policy of leaving unclear whether and how a state would respond to a specific event — most famously US policy on whether it would defend Taiwan from a Chinese invasion. The aim is to deter both attack (by leaving threat plausible) and adventurism (by leaving support uncertain).