Why is the USAF lagging so far behind in building the KC-46 tanker?

Afraid you're right, L/C. They are spending (wasting) so much on this project. In the meantime, the Aussies, Japanese, Italians, etc. have theirs up n' running. With more capability. Also seems like there are no offshore customers for this thing. So disappointed in Boeing.

It's not just the F35, but the USAF culture. The AF is currently run by the "Fighter Mafia" (as opposed to the "Bomber Mafia" back in the Cold War). That means senior leaders were all fighter pilots, so they see fighter planes as the top (and sometimes only) priority. Anything that has more than one engine and is not designed to shoot shit down is an afterthought....even though strategic mobility (which transports and tankers belong) are just as important. No one thinks about logistics until you run out of fuel and bullets......