A Texas Marine stationed in California, would not fight for California. A soldier in New York would not fight against their home in Virginia and a sailor in Houston would not fight against their home state of Florida. The warriors returned to their home states and the states had to reconsider that when they measured troop strength of their new nations. Ultimately, they measured troop strength by how much of the population would return home.
Some states, yes. Others no. The states that seem to have relatively little identity (my experience, and I may not have been in the right spots) include CA, MD, FL, IL. States with a lot of identity include Alaska, Hawaii, KY, TN, VA (away from DC), WY, and of course TX. Still, I suspect rural Appalachia would form a natural affinity group that would ignore the urban welfare class from their own states; with the same in the rural West of CA, OR, WA, ID, MT, WY, and (perhaps) UT; and the same for the rural Sou.