The need to replace the 5.56x45mm and the M4/M16 was arguably proven and accepted years ago. However such replacement by better performed metal-cased ammunition and weapons has been delayed by the promise of combustible/caseless small arms ammunition. And even after changes at the top it seems the US defence hierarchy has again decided to whittle away more years by continued tinkering with the 5.56x45 and the M4/M16.

That resolve could be overturned by executive fiat but otherwise it seems US forces will just have to wait. Probably for at least ten and possibly more than 20 years until the effectiveness and stockpiling of suitable caseless rounds are thoroughly proven. Compliant NATO and affiliated forces are almost certain to follow along.