| Alliance | Founded | Members | Core Purpose |
|---|
| NATO (North Atlantic Treaty Org) | 1949 | 32 (US, Canada, 30 Europe) | Collective defense (Art. 5); crisis mgmt; cooperative security |
| CSTO (Collective Security Treaty Org) | 2002 | 6 (Russia, Belarus, Armenia, Kazakhstan, Kyrgyzstan, Tajikistan) | Collective defense; counter-terrorism; military coordination |
| SCO (Shanghai Cooperation Org) | 2001 | 9 (China, Russia, India, Pakistan, Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, Iran) | Security, economic, cultural cooperation; counter-terrorism (RATS) |
| Rio Treaty (TIAR) | 1947 | 19 Americas (US, most LatAm) | Hemispheric collective defense (dormant; Venezuela withdrew) |
| ANZUS | 1951 | Australia, NZ, US | Pacific security (US-NZ suspended 1986; bilateral AUS-US active) |
| Five Eyes | 1946 | US, UK, Canada, Australia, NZ | Intelligence sharing (SIGINT); not a treaty alliance |
| AUKUS | 2021 | Australia, UK, US | Indo-Pacific security; nuclear subs; tech sharing (AI, cyber, quantum) |
| Quad | 2007/2017 | US, Japan, India, Australia | Indo-Pacific strategic dialogue; not mutual defense |
Regional Economic/Political Blocs
| Organization | Region | Members | Focus |
|---|
| EU | Europe | 27 | Single market, customs union, political integration |
| ASEAN | Southeast Asia | 10 | Economic community, political dialogue, non-interference |
| AU (African Union) | Africa | 55 | Continental integration, peace/security, Agenda 2063 |
| USMCA | North America | 3 | Free trade (replaced NAFTA 2020) |
| Mercosur | South America | 4 full + associates | Customs union, trade |
| GCC | Gulf | 6 | Economic, security coordination |
| ECOWAS | West Africa | 15 | Economic integration, peacekeeping |
Historic / Dissolved
- Warsaw Pact (1955–1991) — Soviet bloc counter to NATO.
- SEATO (1954–1977) — Southeast Asia, US-led.
- CENTO (1955–1979) — "Middle East NATO".
- Comecon (1949–1991) — Soviet economic bloc.
Ad Hoc Coalitions
- Global Coalition vs. Daesh (80+ nations)
- Ukraine Defense Contact Group (50+)
- Proliferation Security Initiative (100+)
Bottom line: "Allies" means treaty-bound mutual defense (NATO, CSTO, ANZUS, Rio) — but strategic partnerships (Quad, AUKUS, Five Eyes) often matter more day-to-day.
Wanderlust World