It’s getting a bit more crowded under the sea in Asia, where Andrew Peterson commands one of the world’s mightiest weapons: a $2 billion nuclear submarine with unrivaled stealth and missiles that can devastate targets hundreds of kilometers away.

Super high-tech submarines like Cmdr Peterson’s USS Oklahoma City have long been the envy of navies all over the globe—and a key component of U.S. military strategy.

“We really have no peer,” Peterson told The Associated Press during a recent port call in Japan.

But America’s submarine dominance in the Pacific is facing its biggest challenge since the Cold War. Nearly every Asian country with a coastline is fortifying its submarine fleet amid territorial disputes stirred up by an increasingly assertive China and the promise of bountiful natural resources.