Boosting the Army & Counterinsurgency

Today, Secretary of Defense Robert Gates announced plans to boost the size of the US Army by up to 22,000 troops. The goal of doing this is to ease the strain on troops who face constant deployment rotations in Iraq and Afghanistan. It seems sensible to do this, as we've asked alot out of our troops, but I'm wondering whether there are alternative motives in doing this?

If we want to continue to garrison the world, then you're going to have to boost the army. We've been told over and over again that successful counterinsurgency requires massive levels of manpower, but I think the more convincing argument is that coordinated intelligence and police efforts are better ways at handling and stopping terrorism. The presence of thousands of troops in a place like Afghanistan is only likely to increase resentment against us. We don't understand Afghanistan, much like we didn't understand Iraq, so it's rather pointless I think to try and simultaneously bring democracy and human rights while stamping out the Taliban and al-Qaeda. It's a fruitless endeavor, and we're likely to spend more blood and treasure trying to achieve the unachievable.

I've got no problem with trying to help out the troops, but the best way to do that is to not send them into places where we don't need to be. We don't need the massive size of the US Army in Afghanistan, we need cooperation from Afghan security forces and we need to give the people a reason to turn their backs on extremism. We could easily reduce the size of the Army by 50% or more if we adopted a more sensible approach to combating terrorism and did away with most of our Cold War era security commitments.