Among global public health advocates, there is a growing concern that President Trump may cut back, or even eliminate, programs that have played a critical role in fighting diseases worldwide. While every administration should strongly review our nation’s overseas commitments, and there are undoubtedly programs that we should cut, I hope he recognizes the success and importance of one in particular: the President’s Emergency Plan for AIDS Relief.

I have been treating patients in Africa and Haiti for 20 years. When I was Senate majority leader in 2003, I led the Senate’s passage of the plan, called Pepfar, on an overwhelming voice vote. It has since been reauthorized twice. President Trump, like his predecessors, will have the chance to put his own stamp on this winning program.

Pepfar was created in a moment of crisis: In the late 1990s, H.I.V.-AIDS was the No. 4 killer worldwide, and No. 1 in Africa. The program aimed to bring reliable, proven measures like antiretroviral drugs, counseling and prevention services to underserved communities around the world — and it worked. Today, Pepfar reaches 11.5 million people with antiretroviral drugs, a 50 percent increase since just 2014. Two million babies with infected mothers have been born H.I.V.-free thanks to Pepfar interventions, and 6.2 million orphans and vulnerable children receive care from the program.

Black and white drawing of children and family in Africa

The program has been able to expand, without a significant change in its budget, because it leverages the latest scientific innovations and reductions in drug prices. As a result, the rate of new H.I.V. infections in Malawi, for example, has dropped 76 percent in just three years. But the work is far from over. One million people worldwide died of AIDS last year, and only about half of those afflicted with the disease are getting proper treatment.

Pepfar’s success is no secret to the new administration. In his confirmation hearing as secretary of state last month, Rex Tillerson called it “a model for us to look to as we’re thinking about other ways in which to project America’s values, project our compassion” to “solve these threats.”

A few days later, though, The New York Times reported that the Trump transition team was asking questions about the value of humanitarian aid in general and Pepfar in particular. For example, transition officials asked, “Is Pepfar worth the massive investment when there are so many security concerns in Africa?”

It’s a fair question, and the answer is yes — in large part because it is such a cost-effective way of addressing those security concerns. After the Sept. 11 attacks originated from a country unable to govern its own territory, buttressing weak states became a key element of America’s national security strategy. The military and intelligence communities were saying that the AIDS epidemic made Africa particularly vulnerable.

Pepfar has helped stabilize much of Africa. In 2015 my former Senate colleague Tom Daschle and I wrote an extensive report for the Bipartisan Policy Center, “The Case for Strategy Health Diplomacy: A Study of Pepfar.” Our researchers compared countries that received Pepfar assistance and, as a control, similar countries that did not.

The findings were dramatic. From 2004 to 2013, political instability and violence fell by 40 percent in countries that received Pepfar assistance versus just 3 percent in similar countries that did not. Measurements of the strength of the rule of law increased 31 percent versus just 7 percent.

And it has paid dividends for America’s image abroad. In 2007, just as Pepfar was taking hold, both Pepfar and non-Pepfar countries in Africa gave the United States approval ratings of about 40 percent, but by 2011 the rating in Pepfar countries had risen to about 80 percent, while in non-Pepfar nations it had risen only to around 50 percent.

Some people are concerned, however, that rhetoric emanating from the White House about foreign aid could spell doom for programs like Pepfar. Others have interpreted Mr. Trump’s executive order reinstating and expanding the “Mexico City policy” gag rule on abortion counseling to mean shuttering Pepfar, though there’s no concrete evidence of that.

Indeed, President Trump seems to favor Pepfar: During the campaign, he was asked in New Hampshire if he would help double the number of people receiving treatment under the program. “Yes,” he said. “I believe so strongly in that, and we’re going to lead the way.”

Vice President Mike Pence is also an avid supporter. In a news release in 2008, he said, “If not addressed, this plague will continue to undermine the stability of nations throughout the third world.” He added, “I believe the United States has a moral obligation to lead the world in confronting the pandemic of H.I.V.-AIDS.”

By embracing and expanding Pepfar, President Trump could make the world’s next generation AIDS-free. He and his administration should render Pepfar not only more efficient but also more strategic by aligning it with clear national security goals. For example, while continuing to focus on eradicating AIDS in Africa, President Trump could deploy additional health dollars to fight diseases and win hearts and minds in countries where traditional diplomacy isn’t an easy option.

Pepfar is the greatest humanitarian effort undertaken by the United States in more than 60 years. But it also makes us safer by making afflicted countries stronger, more stable and more grateful to us. And it can prevent the disease from re-emerging at home in a more virulent form. President Trump has the chance to make America even greater by making the world AIDS-free.

This article originally appeared in The New York Times.