If Congress and President Donald Trump — once again — do nothing about gun violence, they won’t just be do-nothings. They will be active co-conspirators in a nationwide crime epidemic.

An ever-growing number of Americans want something done about the problem after shootings in Dayton, Ohio, and El Paso, Texas, left 31 people dead earlier this month, multiple polls show.

But if recent years are a guide, Congress will put up its collective feet, don its slippers and wait for the furor to die down. Trump most certainly will do the same.

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What are Congress and the president waiting for? So far this year, as of Tuesday, 9,409 Americans lost their lives to firearms and 18,773 were injured. Just last weekend, three people were killed and 24 were wounded in shootings in Chicago.

Why are Congress and Trump OK with that?

After Dayton and El Paso, Trump boasted he would enact meaningful legislation to address gun violence, even claiming he could make it happen because, “There’s never been a president like Trump.”

But, true to form, the president appears to be backing away from that promise under pressure from the gun lobby.

In fact, Trump has started to mouth the usual gun-lobby talking points, such as saying the way to stop gun violence is through better health care for the mentally ill.

It’s true the nation needs better mental health care, but most shootings are not caused by people who are mentally ill. We have a country full of guns that people of all kinds — including some with mental health issues — have easy access to.

Don’t just take it from us. Take it from Arthur C. Evans Jr., CEO of the American Psychological Association, who recently said, “Blaming mental illness for the gun violence in our country is simplistic and inaccurate and goes against the scientific evidence currently available.”

Here’s another false talking point: “The best way to stop a bad guy with a gun is a good guy with a gun.”

In Dayton, police stopped the shooter within 32 seconds, yet nine victims were already dead and 27 were injured. Yes, the good people with guns stopped the shooter, but they couldn’t stop him soon enough. Far better if he had not had an AR-15-style assault rifle and a 100-round drum magazine.

Another example: “More guns are the answer to gun violence.” In reality, countries that have the most guns per capita have the most mass shootings. And the United States, with 4 percent of the world’s population, has an estimated 40 percent of the world’s guns.

A number of bills have been introduced in Congress that would address gun violence.

• A “red flag” bill would allow courts to temporarily prevent someone who is in crisis from having access to firearms. Democrats say they have the votes to move the bill out of the House Judiciary Committee.

• Another bill, already passed by the House, would close some loopholes by requiring universal background checks before individuals could buy guns, including private transfers.

• A bill that would ban private ownership of military-style assault weapons and large-capacity ammunition magazines is gaining support in the House. A Politico–Morning Consult poll conducted after the shootings in Dayton and El Paso found that seven in 10 Americans support a ban on assault weapons, including 55% of Republican voters.

• In another important measure, the House included $50 million in this spring’s appropriations bill to study gun violence and see what measures work best in reducing it. That’s long overdue. Major government studies are how we learned about the best ways to reduce highway deaths; it’s high time to do the same with gun violence.

All of these bills should be easy to pass because the public already supports them. But for Congress to act, the rules of the game will have to change.

Senate Majority Leader Mitch McConnell, R-Kentucky, will have to sense he will lose more Senate seats defending the gun lobby than if he helps reduce gun violence.

Trump will have to be persuaded his support for the gun lobby worsens his chance for re-election.

If we want to reduce gun violence, the rest of us have to act quickly to convince them that siding with the gun lobby is the path to losing their power.

So keep those polls on the issue coming.

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