What if air superiority is not achieved? How does the maneuver force protect itself from air attack?

Scenario.

The USMC has just landed on the beach at Country X.  The landing went off without a hitch and forces are moving inland.  The problem?  The enemy waited until the Marines went feet dry and now they're making a major push to sink every ship in the fleet.

Air superiority is just a dream.  Carriers and LHA/LHDs have moved further offshore to increase warning time for the seemingly endless antiship missiles that are being launched, and a whole gaggle of SU-30 appeared out of nowhere and are contesting any attempt to gain the initiative.

The landing force is on its own.  Additionally the enemy has numerous UAVs.  Some are even Kamikaze types that crash into US vehicles or troop positions once they're spotted.

So how does the force protect itself when the enemy air force has decided to put up a fight?

Other forces have figured it out....

German Gepard

Russian Tunguska M1

South Korean K30

Chinese ZBL09

With the proliferation of UAVs, cruise missiles and the such developing self propelled anti-air systems are a no brainer.  To expect large, relatively stationary setups to keep up with the maneuver force is asking too much.

Luckily the USMC is being presented with an opportunity.  The Amphibious Combat Vehicle is ready made to become a family of vehicles.  A self propelled anti-air system is a no brainer to be a part of that family (along with a mobile gun, recovery, ambulance, and 120mm mortar carrier).

The funding to make this happen MUST be insisted upon.  If he can't be budgeted normally than it should be included in unfunded priorities...and it should be done honestly....if Congress asks then despite what the Defense Sec says we should truthfully answer.

Our business is about to preservation of this country.  The politicians can worry about politics.