By a narrow margin, Arizona voters have given their OK to legalized medical marijuana for people with chronic or debilitating diseases. The decision makes Arizona the 15th state to approve a medical marijuana law. California was the first in 1996, and 13 other states and Washington, D.C., have followed suit.

A U.S. federal appeals court judge says the United States should consider legalizing marijuana. Judge Juan Torruella tells a law school audience in Puerto Rico that experimenting with legalization of marijuana and perhaps other drugs is a better way to reduce drug abuse and crime.

Assume for a moment that California voters approve Proposition 19 on Nov. 2. The state will have just enacted a process for legalizing, regulating, and taxing marijuana use that no one else in the world has ever attempted. But Attorney General Eric Holder, President Obama’s top law-enforcement officer, has said the administration will “vigorously enforce” federal drug laws in the country’s most populous state regardless of the vote. For all the trails that approving Prop 19 would blaze, much of its impact would depend on the extent to which Holder follows through on that threat.

In a dramatic shift of sentiment, nearly half of California's likely voters now want to legalize marijuana use in the state, according to a new Field Poll. Forty-nine percent of those likely voters now support Prop. 19, with 42 percent opposed. In a July poll, 48 percent of those surveyed planned to vote against the ballot initiative, with 44 percent backing legalization.

On Nov. 2, Californians will vote on Proposition 19, deciding whether to legalize the production, sale and consumption of marijuana. If the initiative passes, it won't just be momentous for California; it may, at long last, offer Mexico the promise of an exit from our costly war on drugs. The costs of that war have long since reached intolerable levels: more than 28,000 of our fellow citizens dead since late 2006; expenditures well above $10 billion; terrible damage to Mexico's image abroad; human rights violations by government security forces; and ever more crime.

Drug prohibition is remarkably ineffective, costly and counter-productive -- it has cost people their lives, and put millions behind bars. Is the tide turning?