Finland has joined NATO, dramatically widening Russia's frontier with the trans-Atlantic defense alliance. The Kremlin has described the accession as an "assault on our security."
Finland became the 31st member of the NATO military alliance on Tuesday amid warnings of "countermeasures" from the Kremlin.
Russia's invasion of Ukraine last year prompted Finland — which has a 1,300-kilometer (800-mile) border with Russia — and its neighbor Sweden to drop decades of military non-alignment.
