Joe Biden’s condolences to the community of Uvalde, Texas, where 19 children and two adults were killed in a shooting at Robb elementary school on Tuesday, also came with a demand for action.

“Why are we willing to live with this carnage? Why do we keep letting this happen?” Biden said at the White House on Tuesday evening. “It’s time to turn this pain into action. For every parent, for every citizen in this country, we have to make it clear to every elected official in this country: it’s time to act.”

But despite hundreds of mass shootings unfolding in America every year, Congress has repeatedly failed to pass major gun-control legislation. The hurdles to enacting stricter gun laws in the US are numerous and significant, but activists say they will not give up until change is made.

How often are mass shootings happening in the US?

This year, 213 mass shootings, defined as incidents in which at least four people were shot or killed, have already occurred in America, according to the Gun Violence Archive. In 2021, 692 mass shootings were recorded, in comparison to 610 over the course of 2020.

The US has already seen other devastating examples of mass shootings this month. Less than two weeks before the shooting in Uvalde, a gunman opened fire at a grocery store in Buffalo, New York. He fatally shot 10 people, most of them African American.

What policies have been proposed to address mass shootings?

Gun control advocates have outlined an extensive and specific plan to lower the number of deaths caused by firearms in the US. Those policies include mandating background checks for all gun purchases, including those overseen by unlicensed sellers online or at gun shows, and enforcing a waiting period after someone buys a firearm.

Advocates have also called for expanding the restrictions on people who can legally acquire guns. They say abusive dating partners, those convicted of hate crimes and people with mental illness who pose a safety risk, among others, should be barred from buying firearms. Some have proposed prohibiting gun purchases by people under 21, which may have prevented the 18-year-old shooter in Uvalde from acquiring his weapons.

Some states have already enacted stricter gun laws, but federal legislation would strengthen restrictions nationwide.

Do Americans support stricter gun laws?

There is broad support in the US for certain policies championed by gun-control advocates. According to a Morning Consult/Politico survey taken last year, 84% of American voters support universal background checks for gun purchases.

But opinions are more varied when Americans are asked about their thoughts on stricter gun laws in general. A November poll conducted by Gallup found that 52% of Americans support stricter gun control, which marked the lowest rating on the question since 2014. Support for a ban on handguns also hit a new low in 2021, with just 19% of Americans telling Gallup that they would be in favor of such a policy.

Some of that hesitation may stem from the fact that tens of millions of Americans own guns themselves. Four in 10 Americans live in a household with a gun, while 30% say they personally own one, according to a 2021 survey by Pew Research Center.

Has Congress tried to enact stricter gun laws before?

Yes, Democrats in Congress have repeatedly pushed to strengthen gun laws that could help lower the number of mass shootings in America. Most notably, Congress tried to pass a compromise bill to expand background checks in 2013, months after the devastating shooting at Sandy Hook elementary school in Newtown, Connecticut. That bill failed to overcome a Senate filibuster, as most Republicans and a handful of Democrats opposed the legislation.

After the bill was defeated, then President Barack Obama delivered a fiery speech blaming the failure on the National Rifle Association, which vehemently opposed the legislation and vowed to campaign against any senator supporting it.

“Instead of supporting this compromise, the gun lobby and its allies willfully lied about the bill,” Obama said at the time. “But we can do more if Congress gets its act together.”

What is the path forward for enacting gun-control legislation?

The Democratic-controlled House has already passed bills to expand background checks to all firearm sales or transfers and close the so-called “Charleston loophole”. That loophole, which would increase the amount of time that licensed gun sellers must wait to receive a completed background check before transferring a gun to an unlicensed buyer, allowed a white shooter to target a historically Black church in Charleston in 2015.

But those House-passed bills currently have very little chance of passing in the evenly divided Senate. Republican senators are likely to filibuster any proposed gun-control legislation, and Democrats do not have the 60 votes necessary to advance those bills. The Democratic senator Joe Manchin also made it clear on Tuesday that he would not support amending the filibuster to pass a gun-control bill, meaning Democrats do not have the votes to create a carveout to the rule.

Acknowledging this reality, the Senate majority leader, Chuck Schumer, said on Wednesday that it was unlikely the upper chamber would soon vote on the House-passed bills. “I believe that accountability votes are important,” Schumer said, “But sadly, this isn’t a case of the American people not knowing where their senators stand. They know.”

That doesn’t mean Democrats are giving up on their efforts to strengthen gun laws. Senator Chris Murphy of Connecticut, who represents the Sandy Hook community and has fiercely criticized congressional inaction on gun control, said voters have a chance in November to oust Republicans who oppose reform.

“I’m going to try all day today to try to find some compromise, but this is ultimately up to voters,” Murphy told CNN on Wednesday. “If [candidates] support the current law, if they don’t support reform [instead], then don’t send them back to Congress.”