China fired a missile from a sub into the Pacific Ocean this week. The test occurred while conducting joint drills with Russia. It represents the first open use of this weapon type outside trials. Experts describe this as a new step in China’s maritime power growth. The exercise was an annual event, not a first-time trial. Military sources did not disclose which sub fired it or how far it flew. Neighboring countries now watch Beijing’s submarine strength closely. Details remain limited from defense officials.