Tell me again why 1st Tanks isn't deploying as a unit to Afghanistan?

Amazing.  If you watch the above video you'll see Assault Breacher Vehicles, M-88 Recovery Vehicles, D-9 Bulldozers, MRAPs, and MTVRs. 

What you won't see are M1 Tanks wearing USMC decals.

Why?

Our allies have successfully deployed heavy armor.  We constantly perform mechanized operations.  We assault heavily fortified areas and direct fire weapons would be an asset.

If we won't use them in conflicts like this, then the very notion of Marines and Tanks should be questioned.