I see a lot of comparisons between abortion rights and gun rights, ways the two issues are alike and not alike. For example, almost no one believes the two rights are absolute. Most agree there are acceptable limits for possessing weapons. No one thinks your crazy uncle should have access to a nuclear bomb. Similarly, few people advocate third-trimester abortions, except perhaps when a woman's life is at grave risk.

One strategy the right embraces to deter abortions involves waiting periods. Women, they say, should have to think about their abortion decisions for a couple of days before acting. I disagree with waiting periods as a matter of policy, but most states have them.

Yet when it comes to school kids, America's gun nuts see mandatory cooling off periods as part of a slippery slope. No one should have to wait one hot second in getting a new machine gun in their sweaty little hands. Next thing you know, the gummint will be going after good old-fashioned shot guns, my weapon of choice. (I don't agree with Mark Robinson that assault weapons should be in civilian hands, but I do worry about a fascist takeover of our country. Being armed might be a good idea.)

Would the requirement to wait a day or two dampen the impulse to murder elementary school children? I don't know, though it's a proven approach for reducing suicide. Does a mandatory waiting period it dissuade women from getting abortions? Some studies show a 19% reduction. Others are more ambiguous.

Nonetheless, plenty of states do have waiting requirements. Just not for buying guns. Only four states plus Washington DC have mandatory waiting for firearms purchases.

The American Academy of Pediatrics says:

Under current federal law, there is no waiting period requirement for the purchase of guns. Waiting period laws give law enforcement additional time to perform an accurate background check and create a “cooling off” period to prevent acts of violence or suicide attempts. If sold from a federally licensed dealer, a gun can be transferred to a purchaser before a proper background check is performed. However, the laws do not apply to private dealers in states that do not require universal background checks.

Waiting periods can reduce the number of prohibited people from purchasing guns, along with those who purchase a firearm with the intent of suicide. Waiting periods are an under-utilized, evidence-based strategy for reducing death and injuries.