I don’t believe Russia will challenge the US with conventional forces.
They’d get their ass handed to them.
The Russians have never been a naval power, whether under the Tsars, the Communists, or the current regime. They lost the last naval engagement they were engaged in, during the Russo-Japanese War. Russia has had at most a brown water navy, although Brezhnev did try to make the Soviet Navy world class. However, the Communist economy could not sustain that sort of naval buildup.
So Russia blinked.
