My understanding is that the commerce clause was intended to avoid trade wars between states. Was that the original intent? If so, how would the modern interpretation square with the original intent?
I'm not denying that the scope of the market is global. I'm denying that that fact gives Congress the power to regulate local transactions in that market. What you're essentially trying to argue is that Congress, by virtue of its grant of power to regulate interstate commerce, has the power to regulate things that affect interstate commerce. Not so. Never in any other field of governance has the power to regulate an activity been understood to mean the power to regulate things that affect said activity. That's purely an invention of modern courts.