Mandatory bicycle helmet laws

Commentary on bicycle helmet blog post:
So this is a public health blog. So naturally we're going to be in favor of measures that improve the public's health. Take laws that mandate children and/or adults wearing bicycle helmets. It seems pretty intuitive, right? Wear helmet = less impact if you fall = fewer traumatic brain injuries = improved health population-wide. All for the low cost of a simple bike helmet. This man's blog post doesn't agree. Take a look.

This fact sheet from the National Highway Traffic Safety Administration shows facts to the contrary; bike helmets reduce head injuries and bike helmet laws increase bike helmet use. This CDC MMWR article recommends bike helmet use. Here are some statistics and a summary of state laws from the Bicycle Helmet Safety Institute.

Now, I know that these statistics by themselves aren't a cohesive argument for mandating helmet use, but why the heck not? We mandate seatbelt use, we mandate lots of things that improve your health every day. You don't wake up in the morning without public health touching your life. Why not save especially a child's life by mandating that he or she wear a bicycle helmet while joyfully riding through the neighborhood?