The federal power was always there -- it simply had no cause to be used for the first 100 years of its existence since the was so little trade "among the several states".
Do you believe the states should be allowed to undermine and thwart the interstate regulation attempts by Congress with intrastate commerce that has a detrimental effect on those regulations?
If so, then why did the Founding Fathers have the states to extend that power to the federal government to begin with?
That's absurd!
If there was so little trade among the several States, then why delegate such a power to Congress in the first place?
Do you believe the states should be allowed to undermine and thwart the interstate regulation attempts by Congress with intrastate commerce that has a detrimental effect on those regulations?
If you believe in governing according to the actual words of the Constitution, then Congress only has the power to regulate interstate commerce, not that which substantially affects interstate commerce.
The US managed to get along for about 150 years without the New Deal "substantial effects" test.
If so, then why did the Founding Fathers have the states to extend that power to the federal government to begin with?
Why indeed if there "was very little trade among the several States"? Maybe because your assertion is bogus and there was a thriving interstate and foreign commerce? They simply wanted to facilitate such commerce because it was important to economic prosperity.