"Wherever the interstate and intrastate transactions of carriers are so related that the government of the one involves the control of the other, it is Congress, and not the state, that is entitled to prescribe the final and dominant rule, for otherwise Congress would be denied the exercise of its constitutional authority, and the state, and not the nation, would be supreme within the national field." I've read this case. "Carriers" refers to registered carriers of interstate commerce (in this case the railroad). What's being regulated is the carriers themselves and the rates they charge, not the objects of commerce that they carry.
"What's being regulated is the carriers themselves and the rates they charge, not the objects of commerce that they carry."In that particular court case, yes. But the key point is Congress may regulate intrastate rates if they affect the interstate rates that Congress is regulating.
You would agree, however, that the objects of commerce are affected by the rates?