But do a majority of the people think it is, or should be, the job of the federal government to control these things?
These people elected others to represent their interests in Washington.
Why then, are there no federal laws against prostitution, gambling, suicide, etc.?
Those elected representatives passed the CSA listing marijuana as a Schedule I drug, making it illegal.
Those elected representatives passed the CSA listing marijuana as a schedule I drug, pending to outcome of research to determine what it's appropriate scheduling should be. Were they told when they voted on that the the DEA had no intention of changing the scheduling, regardless of what the results of that research turned out to be?
It is enforced under the Commerce Clause. The CSA has been challenged as to it's constitutionality numerous times in various Federal Circuit Courts and Federal Courts of Appeals (including the infamous, liberal 9th Circuit) and has been unanimously found constitutional.
Only recently has the USSC found any attempt by Congress to pass regulations under the "substantial effects" doctrine to be beyond their authority. That doctrine stems from FDR's New Deal interpretation of the Commerce Clause, and liberal courts have been the most willing to uphold it. Defending the constitutionality of the CSA as a "conservative" position based on it's being considered a socially condervative issue is an exercise in the the ends justifying the means. If you use it to justify the CSA, then you have no grounds to complain about that same doctrine being used to advance liberal agendas.
"I write separately only to express my view that the very notion of a substantial effects test under the Commerce Clause is inconsistent with the original understanding of Congress powers and with this Courts early Commerce Clause cases. By continuing to apply this rootless and malleable standard, however circumscribed, the Court has encouraged the Federal Government to persist in its view that the Commerce Clause has virtually no limits. Until this Court replaces its existing Commerce Clause jurisprudence with a standard more consistent with the original understanding, we will continue to see Congress appropriating state police powers under the guise of regulating commerce."
-Justice Clarence Thomas
Why are you allowed to bring in the concept of "risk", yet I'm not?