China's been steadily upgrading its submarine fleet and weapons to detect those of the US should the two nations go to war.

SEATTLE (AP) — A metallurgist in Washington state pleaded guilty to fraud Monday after she spent decades faking the results of strength tests on steel that was being used to make U.S. Navy submarines.

The world's oceans are changing, with rising temperatures and different salinity levels. Submarine warfare could be directly affected, and it could be harder to detect the vessels in some areas. A new ...