I'm not too sure about NATO serving US interests exclusively. It might appear that way but reality on the ground is something else, militarily and politically.

We do know that decision is made through concesus, i.e., if one of the members doesn' toe the line, a motion is defeated, US or no US.  

The US knows this, eg., when NATO decides to fund a reasearch program (something that happened recently), America backed it up to the hilt but Germany backed out so the project was killed. It's true that the US is often frustrated at the manner some of their motions are often defeated with a simple nay from one member nation but that's the nature of NATO.

But from there to say that NATO member nation troops committed to Afghanistan are inexperienced is taking a bit too far; Gates' whining has the opposite effect on  US allies NATO for that.