Opinion: One need not wonder why the U.S., Russia and now China have invested so much in submarine-launched cruise missiles.

Nearly every war between major powers reveals enduring lessons for future strategists. World War II taught us that airpower had become the new high ground—and that the nuclear bomb was decisive.

The massive Ukrainian drone strike on Russia has strong implications for the future of all warfare. The sophisticated operation taught us that the use of low-cost, highly scalable, lethal drone ...