These are all good points. I ask, then, why not make cuts starting in the DoD? Amongst discretionary spending, the DoD is the single largest part of the budget, taking up something like 55% of spending. President Trump campaigned on a platform of general non-interventionism, yet he wants to ramp up the size of the military, which makes absolutely no sense to me. It seems like the first place to make cuts would be to the biggest slice of the pie. I mean, I know the reason why he won't make cuts to the military - that idea is anathema to republicans, but it also makes very little policy sense.
If you ramp up the military (uniformed) you can reduce the reliance on contractors, which are inherently more expensive to maintain. It actually does cut costs to shift from a contractor model to an employment model when you have the dynamic that the employee can't quit.
I'd also like to point out that the "balanced budget" that you proposed in an earlier post would make the President's infrastructure plan much, much more difficult to accomplish, as borrowing would be curtailed.
Borrowing doesn't have to be cut back in a balanced budget, you just have to allocate income to make the payments.