The Pentagon has more than enough money, and should not be immune from cuts. We are wasting our treasure in lives and dollars on perpetual war that gains us nothing but more trouble and which cannot be sustained. History illustrates the financial collapse of every empire that grew beyond sustainability. We are not immune, and we are choking on the ever-accumulating debt.
Semper Fi! Cuts in personnel can/should start with a reduction of general officer billets.
Next, consolidate the acquisition/logistics function into one directorate.
Fill new civilian DOD positions on a term contracts, not make them permanent from Day 1. The FDIC does that with about 75% of their current workforce, which was beefed up for the banking crisis.
Contracts were set for 2 years, with an agency option for two additional years. Any extension beyond that must be approved through OPM. You won't see any immediate benefits on the cost side, but you'll certainly bend the long-term cost curve on personnel.