>This is why constitutionally no such authority was ever given to the federal government to institute such agencies.

"[The Congress shall have Power] To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes." Article 1, also allows for them to make laws ensuring they can execute that directive.

Congress can pass laws, but not delegate that power to another entity.

> Congress can pass laws, but not delegate that power to another entity.

Congress can, however, make laws whose explicit terms make their effect contingent on external facts, including the actions of officers in particular executive-branch agencies.

I.e. The line item veto.

Yes, exactly.

For reference. http://www.washingtonpost.com/wp-srv/national/longterm/supco...

> Regulatory agencies or any centralized governance becomes a target. This is why constitutionally no such authority was ever given to the federal government to institute such agencies.

“Regulatory agencies” are simply a label for a subset of executive agencies defined by certain traits; I think it would be very hard to argue that the Necessary and Proper Clause does not authorize creating agencies with these traits as a means of exercise of Congress other enumerated powers.

As you say, considering the clause is nothing but the authority to exercise the detail of existing powers http://tenthamendmentcenter.com/2014/09/03/necessary-and-pro...

It would still be questionable that most regulation is actually within the enumerated powers. https://fee.org/articles/are-there-no-limits-to-federal-regu...

If you have to have an analogy it's like comparing a tadpole and a frog.