I can see this playing out. If the US pushed the .308 round in a short action M1. There would have been a need for a newer MBR with a Box fed mag, pistol grip ect...
So, if they just altered the M1 and skipped the M14. What action/type rifle would the free world have standardized on?
FN could have made the choice to abort the FAL insted of scaling it up. Same goes for teh G3.
What were/have been some failed/forgotten .308/7.62x51 rifles thru the 90s?