The Marine Corps is undertaking its most sweeping transformation in decades, pivoting from a focus on fighting insurgents in the Middle East to developing the ability to hop from island to island in the western Pacific to bottle up the Chinese fleet.

The 10-year plan to revamp the Corps, scheduled to be unveiled this week, follows years of classified U.S. wargames that revealed China’s missile and naval forces to be eroding American military advantages in the region.

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