It will be some time, if ever, before we learn the motivation of the assailant in Tucson. What is clear, however, is that a disturbed individual was able to fire off enough bullets to kill six and wound 13 people before he paused to change the clip.

After the Virginia Tech massacre, a few tentative steps were taken to decrease the likelihood of a mentally ill person purchasing a firearm. Those measures were clearly insufficient. We must devise different ways to identify those who are a danger to themselves and to others and to intervene accordingly.

In addition, it makes no sense for a private citizen to carry enough bullets to decimate a school, a shopping mall, or a political gathering. We should support the bill now being introduced by U.S. Rep. Carolyn McCarthy, D-N.Y., which would limit the size of an ammunition magazine to 10 rounds.

The purchase of semi-automatic weapons was banned from 1994 until 2004. While there was no great change in the number of firearm deaths during that decade, there was also no evidence that personal safety was compromised.

Rep. McCarthy’s bill would, in effect, replicate that measure.

Seat belt and air bag legislation have reduced deaths from automobile accidents. Anti-smoking measures and attitudes have decreased deaths from lung disease during the past generation. Congress has just increased the ability of the FDA to make food and medications safer.

When is this country going to reduce the risk of firearm carnage?

Edward Walworth, M.D., Lewiston