NATO

NATO is a military alliance of 32 member countries from North America and Europe, founded in 1949 as a collective defense organization. Article 5 - that an attack on one is an attack on all - creates a mutual defense commitment that has shaped European security for seven decades.

As an alliance system, NATO demonstrates principles of collective defense and deterrence through coordination. Like warning signals in animal groups, the alliance's credibility depends on demonstrated willingness to respond collectively to threats.