The U.S. is in a race to field the capability and develop systems to defend against hypersonic missiles, which China and Russia are developing and testing.
The Air Force must continue maintaining Minuteman III nuclear missiles longer than expected, with the Sentinel successor requiring a major restructuring.
The Marine Corps is also planning to shift its F-35 Joint Strike Fighter procurements to buy more carrier-based F-35Cs and fewer vertical landing F-35Bs.