Krepinevich, Andrew, Barry Watts, and Robert Work

Summary
During the Cold War, the United States defense posture called for substantial forces to be located overseas as part of a military strategy that emphasized deterrence and forward defense. Large combat formations were based in Europe and Asia. Additional forces—both land-based and maritime—were rotated periodically back to the rear area in the United States. This posture was both effective and possible for a variety of reasons. The United States had a clear understanding of the principal threats to its security, high confidence as to where major acts of aggression were likely to occur, and a belief that forward bases were reasonably secure, even in the event of enemy attack.
These conditions either no longer exist or, where they do, are subject to trends that appear most unfavorable to their long-term survival. Today the US military Services are struggling to adapt to an expeditionary era. This expeditionary era has emerged from two defining developments. First, due to the collapse of the Soviet empire in 1989 and of the Soviet Union, itself, in 1991, increasingly US combat forces have been brought home from the overseas garrisons, bases, and ports they once occupied on the periphery of America’s Cold War adversary. Second, there is ample reason to anticipate that future adversaries, having seen Iraq routed twice by US-led coalition forces after they were allowed to deploy unmolested into Southwest Asia, will seek asymmetric ways of opposing the movement of US military forces into their region.
While US power-projection operations are becoming more difficult owing to political, geographic, and resource constraints, there is a growing challenge in the military dimension of power-projection operations as well. This is particularly true with respect to the traditional form of US power-projection operations, which involves deploying and sustaining air and ground forces at or through major ports and airfields. For maritime forces, power projection now implies moving into the littoral to influence operations inland on a far greater scale than was the case only a few decades ago. It also means controlling the littoral in order to sustain US and allied ground and air forces ashore.
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