The core technology is in the engines (US built,) the refueling boom (US built,) the wing and centerline refueling hose and drouges (US built,) and the military-specific avionics (US built.)
The fact that Boeing can rebuild wings for the Fairchild Republic A-10 tells me that the sheet aluminum ain't all that complicated.
Try Titanium on the A10 - Designed to shrug off 23MM AA rounds. McDonnell Douglas got the machines from Fairchild and moved them to Canada, When Boeing bought MCD, they closed MDCAN and moved the technology back south.
EADS is a European conglomerate, not an American company at all. Northrup Grumman is just pimping for them.The US Govt. has failed to complete a major airframe contract to initial bid numbers ( you know the ones that development costs are spread over) on a major airframe in 30 years - Hence the 70 million plus F22, buying 180, bid numbers based on 740 aircraft, ect.. The DOD will end up overpaying on the tankers, the bulk of the overpayment will end up as administrative charges at EADS. We need to keep manufacturing jobs in the US, Not in Europe. BTW any technology transferred to Europe will be sold to China.