For several years now, the U.S. Army and Marines are trying to figure out how their Iraq and Afghanistan experience can be quickly applied to conventional warfare. The head of the U.S. Army, recently commented that units coming back from Iraq and Afghanistan would need about 90 days of training before being sent off to a conventional battle in, say, Korea. Most of that training would be in the form of brigade level exercises, so that the units could get reacquainted with coordinating larger units. The typical operations in Iraq and Afghanistan involves small units (platoons and companies), while conventional warfare is more about battalions and brigades.
The army and marines know from past experience, that each war changes the way a force trains for the next one. World War II left American troops expert at mechanized warfare, amphibious operations, jungle fighting and urban warfare. Lots of that expertise was discarded in the belief that the next war would be nuclear. Korea brought back trench warfare, and by the time Vietnam rolled around in 1965, the nukes were less feared, and everyone was trying to figure out mechanized warfare again. The 1991 Gulf War showed that all the Cold War training worked. American mechanized troops blitzed right through the Iraqis. There were a few small battles where outnumbered American forces handily defeated their determined Iraqi opponents. The 2001 Afghanistan operation was a masterpiece of irregular warfare, and the 2003 invasion of Iraq showed that Americans were still the blitz kings.
But since then, it's been urban warfare and chasing terrorists. Lost in all the headline hysteria and partisan bickering is the fact that American troops have been very effective, but that's partly because they have turned all their energies to mastering a new form of warfare, one that minimizes friendly casualties (including those of nearby civilians) and checkmates the enemy. How do you follow an act like that?
For starters, there's some catch up for tank and artillery crews. Many of these guys have spent a lot of time acting as infantry. GPS guided rockets and shells have meant a lot less employment for the artillerymen who have had work. Those tanks crews that did get to use their vehicles, have become expert at supporting infantry, but have to catch up on a lot of their training in the art of killing other tanks. The marines have passed up on a lot of amphibious and jungle training. However, it's been noted that when these units return to the U.S. (where they stay for at least a year), and train again as artillery or tank crews, they regain their old skills very quickly.
Another big question is, what will the next war most likely be? Korea is still a possibility, although the North Korean forces are falling apart. Korea would involve some mechanized operations, but mainly a lot of infantry fighting. Very little thought, or inclination, has gone into fighting on mainland China. Iran is another problem child, although all those Iranian tanks are no match for American armor and airpower. Invading Iran is talked about much more in the media than in the Pentagon.
One scenario that keeps coming up is something very similar to what has been going on in Iraq and Afghanistan. In other words, more peacekeeping type operations. Still, the generals would feel better if their troops could refresh their conventional warfare skills. Not that it would take long. The last few years have produced some startling advances in computer aided training. A lot of this has come out of the military adopting video game technology in a big way. It works to get greenhorns expert at convoy protection and urban security. It should work to bring back expertise at amphibious and mechanized operations.