You can't destroy railways in other states, they will turn against you.
You shouldn't constantly use railways in other states to provide supplies to a fascist war effort. Besides, who would, in an un-orderly state, be using railroads leading to other states? I doubt dispatching one group of rails would be terrifyingly barbaric if you want don't want to have to wait another 30 minutes to get a longer route.
Besides, we are bombing near Michigan and the ones leading into Michigan, not the ones in the middle of a desert.