If you were to look at a picture of a soldier during WWII and a soldier in either Iraq or Afghanistan today, you would notice many differences. Probably the most noticeable different is the amount of gear that today's soldier carries. We are always trying to improve the way we fight and our body armor has saved many lives.
With that said, we shouldn't be wearing body armor in Afghanistan. We shouldn't be driving around in MRAPs either. These are conventional solutions to an unconventional war. We are treating the symptoms rather than the cause.
Let's start with the decision to upgrade from Hummves to MRAPs. The enemy was building bigger and bigger bombs that were capable of catastrophically destroying a Hummve. So now it is mandatory that we use MRAPs. And guess what? Now the enemy can build bigger bombs that will destroy an MRAP. What's after the MRAP? How big are the next generation of vehicles? MRAPs are big enough--they get stuck on unpaved roads, can't fit through the narrow roads, they are high and bulky and are extremely noisy. Whatever adaptions we make to our vehicles, body armor, etc the enemy will still find a way to kill us. Instead of focusing our efforts on protecting ourselves and adapting to the enemy's operations, maybe we should focus more on rooting out the enemy.
In COIN 101, you are taught that the population is the center of gravity. It's no longer a factory or military base. We are trying to win over the population and make them believe in our cause instead of the insurgent's. All of this is being done, of course, in concert with the local government. The local government and its ideals is what the people are fighting for. So we are trying to connect with the population, person to person. You can almost think about it like a politician trying to win an election. He needs to be a gregarious, sympathetic and passionate leader. Now tell me how this politician would do if he is from a different country than the one he is campaigning in. He wears different clothes. He speaks a different language. He has a different culture and a different religion. He can't campaign forever, he has to go home and visit his family. He would have to work ten times as hard as his opponent in order to be successful.
So when we drive around in our big, out of place vehicles, wear our bulky body armor that makes us look like monsters and spend most of our time on eye sore military installations, I think we are helping the insurgents by isolating ourselves from the population. This is our conventional mindset. This is why industrialized nations lose COIN wars. This is why Afghanistan is the graveyard of empires.