a1bill,
Arizona Republican John McCain, chairman of the Senate Armed Services committee, blasted the block buy strategy, telling CNN that it "leaves taxpayers on the hook for expensive changes to fix problems discovered late in production. And it's one of the reasons that the F-35 is a shining example of how not to conduct a major acquisition program."
The F-35 program is more than $200B over budget from what was advertised as well as being terribly late to the party. The US DoD have admitted they still don't know how it will fare in combat because that hasn't been assessed, yet.
It is the American taxpayers footing the bill for the program miscues to this point, the international folks except for the UK have laid little money on the table, at least one none at all. Some Americans must not mind giving away part of their tax dollars to Lockheed-Martin to fix the numerous problems L-M were responsible for creating in the first place.