I heard the same story, the Air Force purchased the medium format Graphic XL system to replace the Konica Rapid because it was made in the US. I know that in the in 70s there were federal laws that required the DOD to buy American even if the product cost more or not as good as imported products. In the late 60s the Nikon F was just making a name for it's self, but by the mid 70's Nikon and Canon had become the pro brands although Leica, Alpha, Pentex and other brands were quality systems. I think the Army and the Air Force still use Nikon and the Navy Canon, but I guessing.

Paul