It a good idea for a bad reason. Arnie says it's time to talk about legalization, but not because of the harms of the war on drugs or the silliness of treating marijuana differently from alchohol, but because if it were legal it could be taxed and bring in more money for the state to spend.
How about these 10 good reasons to legalize?
Heck the aricle mentions a poll showing 56% of registered voters approve of legalization. If majority support is enough to justify banning gay marriage, why isn't it enough to justify legalizing marijuana?
But most of all, Jacob Sullum here parses why a focus on excise tax revenue is off base when talking about legalization.
From the government's (and taxpayer's) point of view, the real fiscal benefit from abandoning the war on marijuana would come from no longer arresting, prosecuting, and jailing pot smokers, sellers, and growers. Drug law enforcement costs something like $40 billion a year, and marijuana accounted for 43 percent of drug arrests in 2005. That doesn't mean legalizing marijuana would save two-fifths of the money spent on the drug war, since marijuana offenders are much less likely to be imprisoned than other kinds of drug offenders. But the savings certainly would be substantial. And that's not counting all the indirect costs, such as marijuana offenders' legal expenses, loss of freedom, forgone income, and so on.
In short, the focus on the excise tax bonanza that legal marijuana supposedly would bring—a theme that is often emphasized by opponents of the war on drugs—is misplaced. Which is just as well, since I'm not a big fan of excise taxes.