The war has already started, with the ferals doing the dirty work of terrorizing the people. When the people react, for whatever reason, that 20,000 will be a force multiplier on the order of 100 to 1.
The whole plan falls apart when the 20,000 become individual targets. The other fly in the ointment is, if/when there is an economic breakdown, how do the troops get paid, and with what? What happens to their families? That’s when my tagline becomes SOP.
C-Rations worked in WW II, and they were glad to get them.