It was early morning. The sound of a plane woke me up and I thought to myself, “that plane must be flying very low.” I was staying at the (now demolished) Hotel Pennsylvania, across from the Madison Square Garden, midtown Manhattan. I looked at the clock and decided it was time to get up—it was 8:43 a.m. on Sept. 11, 2001. Unbeknown to me, American Airlines Flight 11 was about to crash into the North Tower of the World Trade Center.

I was on vacation with a friend, and we had planned to visit the Big Apple later that day. Instead, we watched live, in horror, as pure evil was unleashed against the country I loved. Terrorists massacred nearly 3,000 people in the attacks alone—and many more as a result—on U.S. soil, by turning commercial airplanes into missiles.

The meticulous work of the National Commission on Terrorist Attacks Upon the United States revealed that the 9/11 terrorists, while working within the immigration system to enter the U.S., committed several violations that could have had them denied (re)entry into the country, such as using doctored passports, incompletely filling out or lying in visa applications, and not updating their tourist visas to student visas.

Have we become more vigilant today? Sadly, no. We have actually made it easier for terrorists to enter in the past few years by opening the doors of our southern border.

U.S. Customs and Border Protection reports that since October 2022, Border Patrol made 149 encounters between ports of entry of people who were on the U.S. government terror watchlist—146 of them at the southern border—compared to 98 in 2022 and three in 2020. While these represent a tiny portion of the people who enter our borders every day, they entered illegally, purposefully trying not to get caught. It took only 19 terrorists to kill 3,000 Americans on 9/11 and many more in the years to follow.

How many more on the terror watchlist may have entered? The number of gotaways—people entering between ports of entry who we know entered but were not stopped—reached more than 637,000 in 2022, meaning there are possibly many more dangerous foreign nationals who have entered our country without us even knowing it. Just last week, Border Patrol agents found backpacks with ammunition and a homemade explosive in Fronton, Texas—a location well-known for illegal crossings.

The immigration policies of the current administration have left our border patrol and law enforcement resources overwhelmed by mass illegal immigration, limiting how much they are able to secure our border between ports of entry. Cartels know that. Criminals know that. Terrorists know that. And they are obviously taking advantage of the situation.

After 9/11, all planes were quickly grounded. The borders were almost fully shut down. My friend and I would only be able to go home several days after our initial return-flight date, and only because we were among a lucky few allowed to return on board the French presidential plane, after President Chirac’s visit.

We do not have to wait for a tragedy to happen again to take common-sense actions. The lawlessness at the southern border must stop now. The border must be secured.

We owe it to the heroes of Sept. 11 not to be negligent again. And what’s going on at the southern border is beyond negligence; it is a dereliction of duty to protect U.S. citizens on American soil.