Never thought I'd say this, but I think the .40S&W is perfect for the military's needs. Since no JHP a larger caliber makes a difference and it is decidedly larger than the 9mm.
It's bad enough that American police were scammed into the .40 short&weak, heaven hope that the military isn't ever saddled with it.
Very similar wound ballistics, with more recoil, less magazine capacity, and higher cost than 9 mm. Oh Boy!
It would be nice to see a return to the .45, but other than for special units, I don't think it's going to happen.