The U.S. Army is applying the lessons of the Iraq war, by training leaders to avoid mistakes made, and embrace ideas that worked. This is not being done in the usual manner, by preparing for the next war by training to operate the same way you did in the last one. No, for the last three decades, the army has been changing the way it remembers, and training its officers to use the past, not just the last war, when they encounter seemingly new problems on the battlefield.
This process really got started when, in the late 1970s, the army sought ways to avoid the years of trial and error in Vietnam, before they came up with a strategy that defeated the local guerillas (the Viet Cong). In other words, the army changed the way it remembers things.
This is very important to many of the troops fighting in Iraq and Afghanistan. Some of them remember their fathers or uncles, who served in Vietnam, complaining about how everything was reinvented back then, even though old soldiers, or marines, remembered doing the same kind of anti-guerilla work before World War II. No one wanted to have all the new ideas and techniques developed in Iraq and Afghanistan, or retrieved from Vietnam, or earlier, experience, lost. In the 1980s, this led to a "Lessons Learned" operation being set up. CALL (Center for Army Lessons Learned) proceeded to capture lots of combat experience from Vietnam, Korea, Vietnam, and even earlier. The CALL researchers soon noted reoccurring patterns, certain ideas and concepts that kept getting reinvented. They were ready when September 11, 2001 came along.
The brigades that went to Iraq during the last six years, always found that their playbook ("doctrine") was constantly changing. Troops that served more than one tour in Iraq or Afghanistan, found that their pre-deployment training was different each time. This was what won the war in Iraq, adapting faster than the enemy could. This "adaptation speed" has now been added to the army playbook. Training exercises emphasize the unexpected, and pressure commanders to cope quickly.
Earlier this year, the army also put wars like Iraq and Afghanistan on an equal footing with "conventional wars. This was done with the publication of a new top line field manual (FM 3-07) "stability operations" (the kind of "small wars" being waged in Iraq and Afghanistan.) The army has always had an FM-7 for "full spectrum operations" (total war, against troops in uniform, armed with a full spectrum of weapons and tactics). Now it is committed to training for both types of combat. The key to this is training the commanders. One discovery in the last decade is that the troops can switch from conventional combat, to irregular type operations, more quickly and efficiently than their bosses. The new training exercises are emphasizing getting the commanders up to speed with their troops. This sort of thing is nothing new. As far back as before the Revolutionary War, it was the troops who saw flaws, suggested fixes and, with varying degrees of success over the centuries, got them accepted and implemented by their commanders. It's another example of how speed is a weapon. Not just speed in moving around the battlefield, but the speed with which you change your tactics, and even your objectives.
The army has simulation technology that makes it cheap and easy to set up a realistic wargame, with brigade, and higher level, commanders, standing in their usual headquarters (everything from a tent, to an office suite back in DC, full of PCs, datalinks and flat panel displays), having to deal with realistic wartime decisions. These are the exercises that involve only commanders and staffs, and these are churning through the many phases of the Iraq war, and creating new situations that might show up in Afghanistan, or elsewhere.
The army also wants to measure how quickly the commanders can switch from conventional, or irregular warfare, and back again. The colonels and generals now have their two playbooks, and over the next few years, they will be tested. So will the battalion, company and platoon commanders, and their NCOs. All this is rather novel in military history. In the past, there have always been armed forces that were more flexible and adaptable than their adversaries. But now this flexibility is being taught, and commanders are being trained to do it, and do it faster.