By 1936, the "Progressive" movement had infected BOTH parties as well as the Supreme Court. "Precedent" is not synonymous with "correct" and nowhere in the Constitution is the Supreme Court given sole determination of Constitutionality. "Precedent" when used in medicine is termed "anecdote" and is dismissed out of hand; they same standard should apply Constitutionally.
The Federalist Papers show over and over again that the commerce clause and general welfare clause were to be read _very_ strictly and narrowly.
The Anti-Federalist papers show over and over again exactly how the to-be-created federal government was going to over-reach its Constitutional bounds. Despite the emotional hyperbole of many of those writings, they were correct.