Do you want to see a perfect illustration of what's wrong with the "Progressive" view of the Constitution? Look no further than the Commerce Clause.
The Commerce Clause is located in Article 1 Section 8 of the Constitution (the section dealing with the power of Congress):
To regulate commerce with foreign nations, and among the several states, and with the Indian tribes
Pretty straightforward, right? This clause gives Congress the ability to regulate commerce among the States. That is, between the States. Specifically, it gives Congress the power to make laws that would prevent one State from inhibiting commerce across State lines. For example, Congress could step in and say that Virginia cannot impose a tariff on tobacco imported from Maryland in order to make it more expensive than Virginian tobacco. The Commerce clause was basically a free trade agreement within the US and among the individual States.
Progressives took a hold of this clause (and the Welfare and Supremacy Clauses) and twisted their original meaning so that they could justify all types of power grabs that were never intended, indeed OPPOSED, by the Framers of the Constitution. Today, we have Federal laws regulating INTRAstate commerce because of this hijacking by the Progressives. (I will add that Republicans have abused this clause too, they are not completely innocent on this but Progressives have far and away more counts against them on this point.) There are literally tens of thousands of pages of regulations that rely on this perversion of the Commerce Clause to exist. Congress has expanded the scope of the clause to the point that it is just a given (in the minds of Progressives and some Republicans) that the Federal Government can do whatever it wants.
It has gotten so bad that Congress was poised (and is still considering) to implement a mandate for individuals to buy Health Care Insurance. The Commerce Clause, which was intended to regulate States, not individuals, has been perverted by some to mean that the Federal Government can mandate someone buy a product or service that they may not even want to buy? For what? To force people to pay into a government managed Health Care industry? That's not what Congress was empowered to do. In fact, James Madison specifically warned against such a power grab and he is credited with being the principle author of the Constitution.
What Congress IS specifically empowered to do is regulate commerce among the individual States. Guess what? That means that they can pass laws that would nullify the States laws preventing Insurance Companies from selling policies across State lines. In fact, that is EXACTLY the kind of scenario the Commerce Clause was written for. Coincidentally, Progressives don't want it. They're arguing against it.
They just don't get it.