If a monster were to attack Chicago, (like Cloverfield) which Army Infantry would respond first?

I am a reservist in the 98th esb signal battalion and it just varies about the state my unit is signal so we would not but say your in Georgia home to the infantry it would probably just range from the 101 airborne to the 2nd infantry but its more than likely the 88th air assault and 101 airborne would be involved a creature of size we would bring in artillery units like I said it just varies.