Reversing a failed policy in just a handful of states is much easier than a big national repeal.

Regardless whether you support marijuana legalization or oppose it, you should back allowing Colorado and Washington State to proceed with their marijuana legalization experiments without federal interference. Why marijuana reformers should support this path is self-evident; but there is a strong case for why even people who honestly believe legalization would a social negative should want to see these local experiments run their course.

To understand why you need to game what happens if the federal government came down hard on Colorado and Washington. The federal government could defy the will of the electorate and stop a legal marijuana industry from existing in these states temporarily, but we would learn nothing and it wouldn’t stop the popular trend in support of legalization. The feds can arrest state-licensed growers but it can’t stop the current political and demographic dynamics which define the issue.

With state reform efforts blocked, energy would turn to changing federal law. While that fight will take much longer given current trends, it will happen someday. Legal retail marijuana sales are coming, the question is will it start as a limited experiment in a few states or come in a big pent-up national sweep with a change in federal law.

If you honestly think legalization will turn out to be a disaster, the former is the least bad option. Reversing a failed policy in just a handful of states is much easier than a big national repeal.

As long as the federal government doesn’t interfere in these states it should quickly become apparent what the impact of legalization will be. People from all over the country will be able to judge it firsthand. If it actually does turn out badly in these early states that would probably be the only thing which could reverse popular opinion and the political pressure for legalization. It would be a quick end to this effort.

Since the country seems determined to eventually legalize marijuana we should allow this small-scale test to take place. If the opponents are actually correct they should see this is as their best opportunity to be proven right and put a stop to this trend before it gains too much momentum. Reform advocates are more than willing to have their arguments put to the test for everyone to judge the results, honest opponents should as well.

Jon Walker is the author of After Legalization: Understanding the future of marijuana policy

Photo by Carolina Biological Supply Company, used under Creative Commons license