HOW CONGRESS CAN PURSUE A REASONABLE GUN DEBATE

› Columbine High School in Colorado: 13 dead, April 20, 1999.

› Virginia Tech: 32 dead, April 16, 2007.

› Sandy Hook Elementary School in Newtown, Conn.: 26 dead, including 20 first-graders, Dec. 14, 2012.

› An Orlando, Fla., nightclub: 49 dead, June 12, 2016.

Now Monday’s atrocity in Las Vegas: at least 59 dead, more than 500 injured when a sniper took aim at outdoor concertgoers from his perch in a 32nd-floor hotel suite.

The geography of American slaughter by firearms spans the nation, while the timeline stretches back at least to the 1966 University of Texas bell tower shootings. Just since Sandy Hook, by one count, there have been 29 shootings in the U.S. in which three or more people were killed. You probably remember the Charleston church murders (9 dead), but what about the Roseburg, Ore., spree (also 9 dead)?

After each of these horrors, the question of what can be done to prevent mass shootings arises. Then it’s dispensed with because the country appears hopelessly divided over gun control. That’s what happened after Sandy Hook: All those children and teachers murdered in their school, yet Congress refused to adopt any meaningful restrictions on gun ownership. So why would this week’s carnage in Las Vegas be the catalyst?

Maybe it won’t. Maybe Las Vegas, the worst mass shooting in modern American history, has no impact beyond its place in the roll call of tragedies. But that would be wrong, because the country is long overdue for a serious debate about firearms and murder.

Let that debate begin with an affirmation that America is suffering from a crisis of gun violence. You see it in mass shootings in public spaces across the country, and you see it neighborhoods in Chicago, where the number of homicides this year has surpassed 500. Nothing will outlaw killing, but doing nothing shouldn’t be an option.

The obstacle is American gun culture. Three in 10 American adults own a gun, and most of those people say gun ownership is essential to their freedom, according to a recent Pew Research Center study. That belief is supported by law: The Supreme Court ruled in 2008 that the Second Amendment guarantees individuals the right to own guns for self-defense.

It’s safe to say repealing the Second Amendment isn’t on the horizon. Putting broad restrictions on ownership, such as banning assault weapons, won’t happen any time soon.

The gun lobby is powerful, and most conservatives embrace ownership as a fundamental right. Certainly, voters have rewarded Republicans in Congress who support gun ownership. Republicans put forth no new legislation after Las Vegas but, tellingly, they shelved for now a National Rifle Association-backed bill that would ease regulations on silencers.

Democrats, who may instinctively wish to ban certain weapons or even limit the number of firearms per household, don’t have the votes, and they alone won’t change the culture. Yet there are steps Congress can take that won’t run afoul of the Second Amendment but could reduce the opportunities for a madman with an arsenal to kill with impunity. Among the possibilities:

› Require background checks for every gun purchase, including those at gun shows and transactions between private parties.

› Limit the capacity of magazine clips to, say, 10 rounds. That would force an assailant to frequently reload or switch weapons, buying time for victims to escape and law enforcement to arrive.

› Require gun makers to modify semi-automatic rifles and pistols so they can’t be fitted with devices that convert these firearms into machine gun-like weapons.

Perhaps none of these steps would have stopped the Las Vegas gunman, though they may have slowed him down. What’s more, tightening federal restrictions on gun ownership and sale could slow the carnage in major cities such as Chicago. Many weapons used by street gangs are stolen. Others, though, are bought illegally by straw purchasers in nearby states. Expanded background checks could disrupt the flow.

Mass shooters are unhinged. No effort to eradicate all violence will succeed. But if there’s a chance to stop some killers, or slow them down until help arrives, the nation should act.