US government tried from the get-go to hold the numbers down. It only got worse after Mc Pain went all schizoid over Boeing offered to lease new tankers to the AF (which would have certainly been more efficient & probably cheaper as well).
In his defense, McCain had some bone headed revolving door action to use as a club...as if US Navy to US Senate wasn't a revolving door that worked for him!
Feds are happier to sink funds into F35s that will be obsolete decades before a good cargo/transport begins to lose its legs.
Unfortunately, but logically, C17 is built to a military requirement that is not readily morphed into commercial use or demand (unless you're Russian or UPS wanted into the tank delivering business).
I assume most "friendly" nations simply expect the US to provide heavy lift when needed (UK, Aus., and India bought in, US fronted a couple of token "NATO" birds, and Quatar has a beauteous fleet of one which will likely never see a military payload).
Gonna be a sad day when the -130s come up short on load and range and the last C5 falls out of the sky.
Good for India that they were first to figure out that it may be time to stock up...I think this buy would make them the second biggest user of the plane after USAF).