Herewith (as promised) a brief comment on brother Rappaport’s splendid earlier post on the “exclusive” Commerce Clause. Here’s the key paragraph:
It is too bad that Congress does not have the exclusive commerce power, because I believe it would be better than the original meaning. An exclusive power would make it less likely that the states would have agreed to the New Deal expanded, concurrent commerce power. Thus, the exclusive power would have been unlikely to have been expanded into the broad scope that the current commerce power has. With a more limited scope, the federal government would have limited authority, as would the states. There would not be two governments exercising the same authority and neither would have complete power to create cartels. This arrangement came close to being followed in the pre New Deal era, when the Court came pretty close to recognizing a limited federal Commerce Power that was largely exclusive. But it is now, sadly from a policy perspective, gone with the wind.
I think there’s pretty powerful evidence to the effect that the Founders did mean the Commerce Clause to be exclusive; it’s just that their idea of what constitutes “commerce among the several states” was so much narrower that ours.