There is no rational explanation for shooting 70 people in an Aurora, Colo. movie theater.

Or, two days earlier, 17 people in a Tuscaloosa, Ala. bar.

Or, last year, 19 people in a Tucson, Ariz. parking lot.

Or, 14 months before that, 42 people at Fort Hood, Texas.

There's no rational explanation for any shooting rampage, including the next one. Yes, there will be a next one. There's no stopping it. But there's no excuse for letting it happen without trying to limit the carnage.

As columnist David Brooks pointed out on these pages Wednesday, that includes finding better ways to identify and aggressively treat mental illness before it manifests itself as barbarism.

Limiting the carnage also means adopting reasonable restrictions on the tools of mass murder.

<NO1><NO>As the U.S. Supreme Court made clear in two recent decisions, the Second Amendment right to own a firearm doesn't preclude regulations to protect public safety.

To that end, California's senators, Barbara Boxer and Dianne Feinstein, favor reinstatement of a federal ban on assault weapons, such as the AR-15 rifle used by James Holmes in Aurora. California outlawed assault weapons after a gunman armed with an AK-47 knock-off slaughtered five children and wounded 28 others plus a teacher in a Stockton schoolyard in 1989.

The federal ban was adopted after Gian Luigi Feri, a one-time Sonoma County resident, shot 14 people in a San Francisco law office in 1993. But the law was allowed to expire 10 years later.

We don't believe that renewing the ban would be inconsistent with the U.S. Supreme Court's rulings. But we recognize that it isn't going to happen any time soon. There isn't enough support in Congress from either party. President Barack Obama and GOP challenger Mitt Romney, meanwhile, are distancing themselves from their past positions on the issue.

There are, however, steps short of banning firearms that can — and should — be taken before the next mass murder.

First, purchasers at gun shows should be subject to background checks, just as buyers in sporting goods stores already are. This loophole is unjustified.

Second, regulate ammunition sales. Holmes was able to acquire 6,000 rounds with the click of a mouse. California enacted a law requiring purchasers of handgun ammunition to appear in person and present identification.

The law is on hold pending a legal challenge. If it's upheld, it will serve the same purpose as a background check: helping police identify people trying to circumvent laws forbidding felons and the mentally ill from having firearms.

Third, outlaw high-capacity magazines, another step already taken in California. Legitimate acts of self-defense don't require 75 or 100 rounds. But from Stockton to Aurora, they have resulted in more shots fired, more wounds and more needless death.

No, none of these steps will prevent the next rampage. But they could reduce the carnage. They could spare a life.