I am not an Alaskan. I live in New York City where we think fall is chilly when we have to wear a cotton sweater. But I have two reasons for wanting to address Ballot Measure 2. One is that Alaska is a red state, and I am a conservative Republican who has been writing for William F. Buckley Jr.'s magazine National Review for more than 40 years. There are good conservative reasons for supporting Ballot Measure 2 — cost, consistency, federalism, and learning the lessons of history.

War is never cheap, and the war on drugs is no exception. According to a 2010 estimate by the FBI and the federal Bureau of Justice Statistics, Alaska spends between $2.5 million and $14.4 million a year enforcing drug possession laws; and in 2010, four-fifths of the ensuing arrests were for possession of marijuana. In Washington, D.C., a few million dollars is lost in a sofa every time a congressman sits down, but in a small state like Alaska such sums add up. Conservatives look for savings wherever they can; the money spent on policing pot is an obvious target.

Conservatives believe that laws should provide clear and consistent rules of the game; laws that are arbitrary or capricious undermine the authority of the law itself. Alaska's marijuana laws as they now exist do not meet this standard. Alaskans approved the medical use of marijuana in 1998. But there has never been a medical dispensary in the state, and home-growing is not an option for most people. So cardholders are driven to the black market. The laws simultaneously beckon them to seek relief, then threaten them with arrest.

The unnecessary burden on sick people is my second, personal reason for offering an opinion on Ballot Measure 2. In 1992, I was diagnosed with testicular cancer. The powerful anti-nausea drug Zofran had just become available, but even it was not enough to control the vomiting that chemotherapy induced. I ended up smoking joints that my wife snagged off her swim coach — an extra effort and anxiety that we did not need just then. Sick Alaskans should be spared this particular problem.

The United States is a huge, discontinuous country, stretching from the Arctic Ocean to Key West. Regional manners and mores differ as much as climate. The formula for effective self-government in a transcontinental republic is federalism, according to which the federal government handles defense, trade and certain basic issues of fairness, while states and communities tailor other laws to what people on the spot want or need. As Abraham Lincoln put it in 1858, "I do not believe in the right of Illinois to interfere with the cranberry laws of Indiana, the oyster laws of Virginia, or the liquor laws of Maine." This division of labor is a profoundly conservative insight. Visionaries, demagogues and bureaucrats believe they know what is best for 300 million people. Conservatives so far as possible believe in letting people mind their own business. Marijuana laws above the 50th parallel should be set in Alaska, not Washington, D.C.

Most marijuana prohibitionists have good motives. Any psychoactive drug can be abused (Ballot Measure 2 recognizes that minors should not use marijuana, and that adults should not use it before they drive). By keeping marijuana illegal, prohibitionists hope to prevent any possibility of damage. But history shows that complete prohibition is the wrong way to go.

The most abused drug in America has always been alcohol. Temperance reformers at the turn of the 20th century were not bigots or killjoys, but serious men and women responding to real social problems caused by addiction and over-indulgence. But Prohibition, in force from 1920 to 1933, imposed on the majority who drank responsibly, drove the determined to speakeasies and bootleggers, and caused organized crime to flourish. Marijuana prohibition, serving the same good motives, accomplishes the same unfortunate ends.

The founding fathers never made such a mistake. The first Secretary of the Treasury Alexander Hamilton, who is commonly thought of as the big government man of his time, recognized that drinking was a problem in late 18th-century America. "The consumption of ardent spirits," he wrote in 1790, "is carried to an extreme which is truly to be regretted." But his solution — the farthest that any of the founders was willing to go — was to tax it. Alaskans could profit from the founders' example.

Richard Brookhiser is a senior editor of National Review and a historian of the nation's founding fathers.