George Mason University President Ángel Cabrera. (Jahi Chikwendiu/The Washington Post)

The number of people from other countries who choose to come to the United States to study is declining, and that should worry all of us.

According to the Open Doors report just released by the Institute of International Education, new international student enrollment declined for the second consecutive year in 2017-2018, accumulating a drop of about 10 percent since its peak in 2015-2016.

The total number of international students grew marginally by 1.5 percent because of the tail effect of four strong years prior to 2016 and because graduates from earlier years are allowed to stay and work for up to three years under the Optional Practical Training program, which was expanded in 2016. If we exclude these graduates, the total number of international students who are actually enrolled is already down 1.3 percent.

The causes of this worrisome decline are likely multifaceted. But what is clear is that the Trump administration’s tough talk on immigration, walls and travel bans is not helping. While other countries work hard to attract international students, we are managing to send a message that talented foreigners are not welcome here, just when we most need them.

Higher education has long been one of this nation’s greatest economic assets, attracting the brightest and most promising minds from around the world, fueling science and innovation, creating jobs and spreading economic prosperity. Some of the most successful start-up companies in the United States had at least one immigrant founder, including Uber and SpaceX. Two of America’s most iconic software companies, Microsoft and Google, are led by Indians who came to the United States as graduate students.

International students have choices. As a Spanish immigrant who came to the United States to study on a Fulbright scholarship and later returned to lead a major U.S. research university, I know this quite well: If students don’t feel welcome here, they’ll go elsewhere.

While we double down on our anti-immigration rhetoric, our neighbors to the north are eating our lunch. They are expediting student visas and creating pathways for certain international students to stay in Canada upon graduation. As a consequence of their efforts — and ours — Canada’s international student numbers surged by 20 percent in 2016-2017.

International students don’t take away resources from American students. On the contrary, they create economic value and jobs, contribute to talent pools in critical disciplines, pump resources into our universities, and enrich our campuses intellectually and culturally. In 2016-2017, students from outside the United States contributed $42 billion to the U.S. economy. In Virginia, 22,000 international students — more than half of them at Virginia Tech, George Mason University and the University of Virginia — pumped an estimated $711 million into the state economy, much of it in the form of out-of-state tuition that helps subsidize the education of state residents.

American universities are committed to global engagement, educating international students, sending students abroad, collaborating in cross-border research and teaching students to be productive in an interdependent and interconnected world. We are trying our best to send that message through initiatives such as the Declaration on University Global Engagement, which is being endorsed by institutions and associations at home and overseas.

But our voices alone won’t be loud enough. It is urgent that our public discourse reflect our tradition of collaboration and global engagement. We must reassure the world that our universities remain open to the rest of the world and eager to engage with the best minds, wherever they may come from.

Ángel Cabrera is president of George Mason University.