I’ll never forget where I was when news broke of the horrific mass shooting that took place at Columbine High School. I had just been re-elected to Congress, and I remember standing in my Capitol Hill office watching as the horrors of that day unfolded. As the mother of two young daughters at the time, all I could think about was them.

While I knew neither of my girls was at Columbine, as a parent — in that moment — it didn’t matter. The sudden fear I felt for their safety was very real. And it’s the same fear that millions of other parents across this country have felt in the years since.

Enough is enough. It’s upon us, as a nation, to come together and demand change.

There is no greater threat to the safety and well-being of the American people than the threat of gun violence. And Congress has no greater responsibility than to protect the people it represents.

While no two mass shootings are the same, one common thread that unites most of these horrific events is the use of high-capacity magazines. According to reporting from The Washington Post, more than half of all recent mass shootings in this country — including all three shootings last month — involved the use of high-capacity magazines.

As a fourth-generation Coloradan, I’ve met with ranchers and sportsmen from across our state and none of them use a high-capacity magazine to hunt. As a sitting member of Congress, I have talked to law enforcement officers from across the country and none of them carry a 100-round drum.

Yet, despite there being no legitimate reason why anyone should need a high-capacity magazine — capable of holding 30, 40 or even 100 rounds — they remain legal, and readily available for purchase in 41 states.

Since the nationwide ban on high-capacity magazines expired in 2004, their use in the commission of crimes has increased three-fold. And because they allow shooters to fire more rounds, more quickly — and kill more people — before having to stop and reload, they have become increasingly popular among those looking to cause us harm.

Last month, a gunman in El Paso, Texas, used a semiautomatic assault rifle with a high-capacity magazine to kill 22 innocent people inside a Walmart store. Similarly, a gunman who opened fire at a crowded festival in Gilroy, California, was found to have had more than a half dozen high-capacity magazines in his possession when police searched him after the shooting.

No incident, however, makes a stronger case for banning high-capacity magazines than last month’s shooting in Dayton, Ohio, where a gunman, armed with an AK-47-style assault rifle and a 100-round magazine drum, was able to fire 41 shots, killing nine people in just 32 seconds.

While, amazingly, officers in Dayton were able to take that shooter down in just 32 seconds after he started firing, it still wasn’t quick enough to save the nine lives we lost that day, or protect the 27 others who were wounded.

Imagine, however, if that shooter in Dayton was forced to stop and reload after firing just 10 rounds. Given law enforcement’s quick response, he probably never would have gotten off that eleventh, twelfth or forty-first shot.

While there is no one single piece of legislation we can enact that will fully prevent these types of attacks from happening, experts agree that one of the most effective steps we can take right now to protect our communities is to reinstate the nationwide ban on high-capacity magazines.

Nine states, including Colorado, and the District of Columbia have already acted to ban high-capacity magazines within their borders, and studies have shown that these states have all experienced fewer mass shootings since those bans took effect. There is no reason why we shouldn’t immediately expand those bans nationwide.

On Tuesday, 41 members of the U.S. House of Representatives will gather in Washington to vote on a bill U.S. Rep. Ted Deutch and I introduced to once again ban the sale or possession of magazines capable of holding more than 10 rounds.

In addition to banning the sale of any additional high-capacity magazines, this bill would also make federal funds available to buy back any high-capacity magazines purchased before the ban goes into effect.

We know that this bill alone will not prevent all future attacks, but it can help make them less deadly. Getting these high-capacity magazines off our streets is one of the most important and simple steps we can take to better protect our communities — and it’s critical that Congress act now to approve this bill immediately.