We have a very wide array of threats pointed towards us:
Greek preemptive strike
Threat: F-35s, Rafales, Vipers, coyotes
Counter: Advanced layered anti-air defense, second strike capability, air superiority jets, mass precision MRBMs
Iranian missile bombardment
Threat: Mass MRBM and long range kamikaze drone strikes
Counter: Something like Iron dome for major population centers, point defense for bases, MRBMs and long range kamikaze drones for second strike, submarines for trade interdiction in the Gulf of Basra.
Assadist Attack
Threat: Chemical WMDs, SCUDs, ATGMs, militia
Counter: Something like iron dome, TB-2s, APS equipped armored units.
YPG Zerg Rush
Threat: Low tier AA, Hamas-ian tactics (like 7 oct), tunnels
Counter: Bunker-buster munitions, armored units, local proxy forces, TB-2s, mass detention centers, lots of yellow bags
American Showdown
Threat: Whatever those unhinged SOBs will bring
Counter: Making it costly to attack and nuclear ICBMs/second strike. Nothing less qualifies.
As you see, we have much to prepare for. It's not like Japan where their only problem is China, or even Britain where they can just make do with the navy. I can't think of any other country that has such varied selection of threats.
And that's not even counting our future airbases in the Horn of Africa, the Gulf, Africa or Central Asia.