One of the enumerated powers cited by advocates of the modern monster-state is the Commerce Power. This derives primarily from two sources:
(1) the Constitution’s grant to Congress of authority to “regulate Commerce . . . among the several States” and
(2) the Constitution’s grant to Congress of authority to “make all Laws which shall be necessary and proper for carrying into Execution the foregoing powers. . .”
According to promoters of the monster-state, those constitutional phrases go further than allowing Congress to regulate trade among the states. They also allow Congress to control manufacturing, wages, agriculture, crime, mining, land use, firearm possession, and a range of other activities.
The problem with defining "commerce" is that anything that someone values, because s/he would spend money on it, can be defined as "commerce". But what really threw the chains of the Constitution off was the creation of a centralized bank. Because the bank was authorized to issue money that had a legally-enforced value, it was necessary for the federal government to enforce its value wherever it was used, a clearly unconstitutional expansion of federal power.
What has happened is that the commerce clause has been twisted to mean any interaction where one or both parties are benefited. Since one major reason people interact is because they want to interact, all interactions are deemed "commerce".
The best way to restrain the commerce clause is to restore the rights of states to protect their sovereignty by repealing the 17th Amendment.