On 29 March 2004, seven states joined NATO (Bulgaria, Estonia, Latvia, Lithuania, Romania, Slovakia, Slovenia).
What happened
- Baltic membership brought NATO to a direct border with Russia.
- It consolidated Euro‑Atlantic alignment.
- Encirclement narratives intensified in Russia.
Why it matters
- Freedom of choice vs spheres of influence became structural.
- Deterrence and NATO‑Russia relations gained weight.
Key point
It defined the perimeter of Euro‑Atlantic Europe and the friction terrain with Moscow.