The difference is that the US can quickly switch to another carrier in case of problems. Not so easy when you have the infrastructure involved with aircraft.
On one hand I like the idea, because it essentially means that the European taxpayers would be subsidizing our military, since their taxes went into the subsidies that lowered our cost for the aircraft. On the other hand, bidding should be done with fair competition, and one of the bidders being subsidized isn't fair.
It's not as easy to switch your supply chain company mid-stream as one may think.
If the DHL supply chain broke down, it would cause major disruptions.