Russia already has the second most capable submarine fleet in the world after the US, Harris admitted, and he warned that their capabilities were likely to rise in the coming years as the US submarine force falters.

Currently, Foreign Policy notes, the US Navy’s shipbuilding plan calls for a fall in the number of attack submarines from 52 to 41 by 2028 before “gradually clawing back to 50 by 2044.”

As the number of US submarines is expected to fall, China and Russia are expanding their submarine forces. Russia has expanded a naval base to allow for new ballistic-missile submarines in the Northern Pacific.

At the same time, Moscow has also undertaken a serious push for the expansion and modernization of its submarine fleet — including the introduction of new submarine models in both Europe and Asia.

This expansion of the Russian submarine fleet includes more aggressive submarine posturing throughout the world.

The US had to recently announce plans to reopen a submarine base in Iceland following reports of Russia operating submarines in the North Atlantic at Cold War-era levels.

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