As he winds down a remarkable Pentagon career – overseeing two long and very costly wars, wrestling with a military-industrial complex resistant to his budget moves aimed at questionable weapons, and shaking up the senior officer corps – Defense Secretary Robert Gates has a message for his successor.

“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 [Douglas] MacArthur so delicately put it.”

In referring to Iraq and Afghanistan, as he did elsewhere in his speech to cadets at the United States Military Academy at West Point Friday, Defense Secretary Gates was not directly critical of the man he replaced – Donald Rumsfeld – or of the Bush administration’s leading an invasion of Iraq now generally acknowledged to have been based on faulty reasoning, insufficient preparation, and – initially, at least – poor execution.

That’s not Gates’s style. And in fact, Rumsfeld’s inclination was to take Iraq with as few troops as possible, while many of those in the Bush administration predicted a quick victory. No “big American land army” for them.

But Gates’s message was clear: The US military services, as well as the elected and appointed civilians who send them to war, need better ways of foreseeing and preparing for national security threats.

“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’,” he said. “Just think about the range of security challenges we face right now beyond Iraq and Afghanistan: terrorism and terrorists in search of weapons of mass destruction, Iran, North Korea, military modernization programs in Russia and China, failed and failing states, revolution in the Middle East, cyber, piracy, proliferation, natural and man-made disasters, and more.”

“And I must tell you, when it comes to predicting the nature and location of our next military engagements, since Vietnam, our record has been perfect,” he quipped. “We have never once gotten it right, from the Mayaguez to Grenada, Panama, Somalia, the Balkans, Haiti, Kuwait, Iraq, and more – we had no idea a year before any of these missions that we would be so engaged.”

“There has been an overwhelming tendency of our defense bureaucracy to focus on preparing for future high-end conflicts – priorities often based, ironically, on what transpired in the last century – as opposed to the messy fights in Iraq and Afghanistan,” he said.

The odds of repeating another Afghanistan or Iraq – invading, pacifying, and administering a large third world country – may be low, Gates said. The careful US response to the current trouble in Egypt, Libya, Iran, and elsewhere in the region attest to that. And it may well be that, as Gates told these soldiers-in-training, that “the Army also must confront the reality that the most plausible, high-end scenarios for the US military are primarily naval and air engagements – whether in Asia, the Persian Gulf, or elsewhere.”

But his recollection of Gen. MacArthur’s famous warning – given to President John F. Kennedy in 1961 as the US buildup in Vietnam was beginning – was a sober message for the young men and women about to become the next generation of US military commanders. As Gates pointed out, more than 80 West Point graduates have fallen in battle since 9/11.