Why are guns more ethical than weed?

In arguing against gun control, John Stossel writes:

The Centers for Disease Control did an extensive review of various types of gun control... It found that the idea that gun control laws have reduced violent crime is simply a myth.

I think I could substitute "Drug Policies" for "Gun Control" and that statement would be just as accurate.

It seems that his main point is that gun control doesn't work and that gun control is a kind of modern day Prohibition. There's a quote in his article that says:

"There's guns everywhere," said another inmate. "If you got money, you can get a gun."

I don't doubt this or aim to argue his conclusions. But it seems an exact parallel to the so called War on Drugs. In the quote above, replace "guns" with "drugs" and it's just as salient. I think the statistics that support the failures of the drug war are probably more compelling than anything the CDC has on guns. So stop the prohibition of drugs! It was ineffective for booze and guns, so lets stop fighting it.

So where does this argument break down? I know the libertarians are down with me, but what about social conservatives...beyond just 2nd Amendment talk. Why are guns more ethical than weed?