Risk is the elephant in the living room that you're asking me to ignore. But I'll assume that you're searching for the constitutional/legal basis for continuing prohibition?
Simply put, a majority of the people don't want marijuana and the other illegal drugs in society. They also don't want prostitution, child porn, unrestricted gambling, suicide, open borders, gay marriage, and a whole slew of other activities. These people elected others to represent their interests in Washington. Those elected representatives passed the CSA listing marijuana as a Schedule I drug, making it illegal. 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.
Now, you can sit there and type away as to how the people are wrong, how the people are ignorant, how the people have no right to tell you what you can and can't do, and how (in your opinion) it is unconstitutional. Maybe one day enough people will agree with you and vote to overturn the existing constitutional laws. Until that day comes, marijuana will remain prohibited.
But, I also think that you need to be fair in clarifying your position. Based on the structure of your argument, it sounds as though you would like all drugs, including prescription drugs to be legal. And you would probably want the FDA eliminated? It really isn't just marijuana with you, is it?
Wouldn't it be fairer to people to understand just what they're getting into if they buy into your arguments? Or is it your intent to deceive?
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 Court’s 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
This is about federal law. If anyone is being deceptive, it is those who insist that anything short of absolute control by the federal government is a free-for-all.