"We can’t know with absolute certainty what the future of warfare will hold, but we do know it will be exceedingly complex, unpredictable, and – as they say in the staff colleges – “unstructured.
(…) The need for heavy armor and firepower to survive, close with, and destroy the enemy will always be there, as veterans of Sadr City and Fallujah can no doubt attest.  And one of the benefits of the drawdown in Iraq is the opportunity to conduct the kind of full-spectrum training – including mechanized combined arms exercises – that was neglected to meet the demands of the current wars.  Looking ahead, though, in the competition for tight defense dollars within and between the services, the Army also must confront the reality that the most plausible, high-end scenarios for the U.S. military are primarily naval and air engagements – whether in Asia, the Persian Gulf, or elsewhere.  The strategic rationale for swift-moving expeditionary forces, be they Army or Marines, airborne infantry or special operations, is self-evident given the likelihood of counterterrorism, rapid reaction, disaster response, or stability or security force assistance missions.  But in my opinion, any future defense secretary who advises the president to again send a big American land army into Asia or into the Middle East or Africa should “have his head examined,” as General MacArthur so delicately put it."
 

                                                                                                                                                          Robert Gates, West Point.