If you think the laws themselves are faulty, then argue against their merit. But arguments of the form "if we removed laws, less laws would get broken" have always seemed somewhat vacuous to me.
Edit: Given the downvotes, I'd love to have a discussion with someone who disagrees.
Start with the facts that this is supposed to be a free nation, a republic with representational democracy, putatively making our own laws.
Now consider that a large fraction of the population is in prison for these very crimes, more so than anywhere else in this world.
This should suggest (although not prove) that the government is imposing its own will, overriding the wishes of the people whose right it is to determine the laws (through their representatives).
I'm reminded of the old 55mph speed limit laws. States would be tested by the federal government; if it was found that more than 50% of drivers exceeded 55, the state could lose federal highway funding. It seems to me that if more than half of the drivers exceeded the speed limit, well then, that's pretty much the same thing as having a referendum with a majority of voters saying that the speed limit is too low.
I understand your argument, but I don't think it's correct. In a democracy, there is no theoretical reason why 49% of the population wouldn't end up in jail. I certainly don't think this would be a good thing, but pure, untainted democracy does nothing to prevent it. You say "if more than half of the drivers exceeded the speed limit, well then, that's pretty much the same thing as having a referendum with a majority of voters saying that the speed limit is too low", but that's really a straw man, because nowhere near half of all Americans are in prison.
And in our case, those in prison are not drawn uniformly from the American population. Prisoners are disproportionately from a minority (intended in the "not majority" sense, not in the skin color sense, though I suppose in this case either applies) subculture, and unfortunately, that subculture glorifies many types of criminal behavior, most of which I imagine you wouldn't favor legalizing.
Again, it's perfectly valid to say that drug laws are wrong and here's why, and that if your ideas were implemented, incarceration rates would be much lower, and that this would be a good thing. All I'm disagreeing with is the general notion that saying laws should be abolished simply because doing so would lower crime rates isn't persuasive. I mean, we could get rid of all the laws, and then the incarceration rate would be zero, but something tells me you wouldn't like that.
Edit: Given the downvotes, I'd love to have a discussion with someone who disagrees.