I don’t think they’d “risk” sending in the military to enforce federal law against citizens. They still would want to maintain the veneer that the military backs the president.
I wish I could believe that the military would turn on Pres. Obama. Unfortunately, I don’t. I think they’d play this as a “rogue” state government and use force against them. And I think that the military would obey their orders.
There’s that little problem of Posse Commitatus. Not that they’d let that stop them if they thought they could get away with it.