Chicago struggles to cope with one of the nation’s largest illegal gun markets because it sits next to states such as Indiana and Missouri that have lax gun laws.

Many of the guns that turn up at Chicago crime scenes originally were purchased legally in those states.

Now, there is a movement to turn downstate counties into mini-Indianas. Sheriffs in many of those counties say they will refuse to enforce laws designed to reduce gun violence.

You can bet that will make it even harder for Chicago to make its streets safer.

EDITORIAL

In Illinois, 63 counties and municipalities have declared themselves gun sanctuaries where authorities won’t enforce at least some gun laws, according to a tally by Reuters. On Monday, downstate Effingham County adopted a resolution to ban state Firearm Owner’s Identification cards, which are required by state law for owning a gun.

This new and growing enthusiasm for creating gun sanctuaries is a reminder that reducing gun violence takes more than passing new laws. Gun safety advocates also have to do a better job of convincing skeptics that their only aim is to reduce gun violence, not to take guns from hunters and others who use firearms for legitimate purposes.

As we learned the hard way during Prohibition, a law must enjoy public support to be effective. And gun safety advocates clearly are not doing a good enough job of enlisting the support of people who live in gun sanctuary jurisdictions.

A smarter approach to selling gun safety — emphasizing an argument that resonates beyond those already committed to the cause — proved effective last year in convincing the state Legislature to pass a law requiring the certification of gun shops. GPAC Illinois, a gun violence prevention group, successfully made the case to lawmakers and parents that their interest was simply to make all children safer, said Kathleen Sances, president and CEO of GPAC Illinois.

Downstate gun sanctuary enthusiasts, who proudly say they are patterning their laws after sanctuary city laws on immigration, may not fully appreciate the connection between lax gun laws outside Cook County and Illinois and the shooting deaths of innocent children in Chicago. They sadly may believe instead the propaganda of the National Rifle Association that every gun law is part of a lefty plot to confiscate every gun in the country.

Ironically, many of the Downstate counties and towns that endorse the notion of becoming gun sanctuaries also are the places where people are most likely to use guns to commit suicide. To address this problem, the state in January adopted a “red flag” law, which allows a family member to petition a court to temporarily remove guns from the home of somebody who might be a danger to himself or others.

Will the sheriff’s police in gun sanctuary counties really refuse to enforce this wise and compassionate law?

The gun sanctuary movement is spreading across the country, and now includes communities and counties in Oregon, Colorado, Nevada, New Mexico and South Carolina.

In Washington state, more than half the county sheriffs say they won’t enforce a law that voters approved in November to raise the minimum age for buying a rifle to 21. The new law also beefs up background checks and lengthens to 10 days the waiting period to buy some guns.

At least five people were killed and 23 were wounding from Friday through Monday in shootings across Chicago.

Our city is awash in illegal guns. It does not need more, from wherever they might come.

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