I swear, its amazing how incompetent the military in zombie horror fiction must be. If ever there were an opponent you'd want to use special weapons & tactics for (not S.W.A.T. in the police sense), it's zombie hordes.
Screw most small arms & artillery; thet the sharpshooters do their work picking off zombies one at a time from 1000 yards with all the ammo they want and good reloading teams: they won't have to move unless in danger of being overrun, because zombies don't shoot (except for a very rare few).
Otherwise, use water cannon to herd them or draw them into killzones with bait (trained volunteers), then light them up with:
- Flamethrowers
- Napalm
- Fuel air explosions
- Acid sprays (to be developed)
- Daisy cutters & bouncing bettys
And the list goes on...shaped charges with copper plates, for instance, can cut a huge swathe through massed zombmanity, as would good old fashioned chain/canister/grapeshot If nothing else, their mobility would be impaired as they get cut in half...and slow zombies are easier to kill.
Even at least one of the new non-lethal weapons systems out there would be useful: the goo guns that spray adhesive foam.
Controlled demolitions of abandoned buildings could clear blocks at a time, crushing them under tons of debris.
(I do admit aerosolization could be a risk, but thats what evacuations are for.)