You may have seen in the news that elected officials in Washington, D.C., are working on next year’s federal budget. One of the ideas that has been floated is to make deep cuts in foreign aid—the investments that America makes to help other countries fight poverty and disease.

That would be a big mistake.

For one thing, these programs amount to less than 1 percent of the federal budget. For anyone worried about the budget deficit, cutting 1 percent will not make a dent.

More importantly, these programs give American taxpayers a phenomenal return on investment, one of the best anywhere in government. They do this in three ways:

• Making Americans safer and the world more stable
• Creating jobs at home and promote trading partners that will buy American goods
• Saving lives and building up health systems so other countries can take better care of their people

Together these three points make what you might call the strategic case for aid—the argument that aid helps the countries that give it as well as those that receive it.

To be honest, the strategic case is not what prompted Melinda and me to get involved in this work more than 17 years ago. We were moved by what you could call the moral case: the idea that it is terribly unjust that people in poor countries—especially children—die of diseases that can be prevented. That is still the main thing that drives us today. But over the years we have come to see the compelling strategic case too. And we have found that people often support aid who aren’t convinced by the moral argument but are by the strategic one.

In this post I want to focus on point #1 above. I’ll come back to #2 and #3 in subsequent posts.

Let’s look at how promoting health and development keeps Americans safe.

Preparing for the next epidemicYou may remember the Ebola epidemic of 2014–16. It killed more than 11,000 people in three West African countries. Each of those deaths was a tragedy, but the epidemic could have been far worse. If it had spread to neighboring Nigeria, home to more than 180 million people and a busy international travel hub with daily flights to the world’s capitals, it would have been very hard to contain. It could have easily jumped the Atlantic and infected Americans, and spread throughout Europe or Asia.

Why didn’t that happen? One key reason is that a number of health workers were stationed in Nigeria as part of the global campaign to stamp out polio. As the Ebola epidemic took hold, they were quickly reassigned from polio to Ebola. They already had a system in place for identifying possible cases, tracking them, and reporting the data to people organizing the response. They helped contain the disease and keep it from spreading farther than it did.

The polio eradication program helped stop Ebola and saved countless people, including Americans. Its biggest public funder? The United States government.

In addition, Ebola may have been only a preview of what is to come. The next epidemic—say, a virulent flu as bad as the Spanish Flu of 1918—could be far worse. Epidemiologists estimate it could kill 30 million people, more than three times the population of New York City.

Funding from the U.S. government helps keep that from happening. It helps other countries strengthen their health systems so they can identify dangerous diseases and contain them before they get out of control.

It is no accident that the Ebola epidemic hit hardest in three countries—Guinea, Sierra Leone, and Liberia—with especially weak health systems. Helping them improve makes it more likely that we can prevent a worldwide epidemic that destabilizes entire regions of the world and kills tens of millions of people.

Stabilizing vulnerable countriesPreventing pandemics is one specific way that U.S. funding makes Americans safer. There is also a broader point here: by fighting poverty and disease, we make the world a more stable place.

For example, both evidence and common sense tell us that when people don’t have reliable food supplies, they will pick up and move someplace else—becoming migrants or refugees—and that leads to more instability. Look at the countries with the least reliable food supplies in the world: Sudan, South Sudan, Eritrea, Burundi. Each of them is either at war or recently emerged from conflict.

Syria is another tragic example. In 2007, the country suffered the worst drought in its history. More than 1 million people fled rural areas for the cities, where they hoped to find food. This migration stoked political tensions and created the foundation for the horrific civil war that continues today. Of course that war has many causes, and not every drought-stricken country will become another Syria. But it is clear that the world is not a safer place when more people are going hungry—and that when we strengthen food and farming systems, we tackle some of the root causes of migration and instability.

Improving health is another way to make countries more secure. One of my favorite all-time examples is PEPFAR, the program America launched in 2003 to stop the spread of AIDS. Today it provides life-saving medicine for more than 11 million people living with HIV in some of the world’s poorest countries. Those 11 million people are teachers, health-care workers, and police officers—people who build strong, self-sufficient societies. So it should not be surprising that in countries where PEPFAR has a presence, political instability fell by 40 percent between 2004 and 2013. In non-PEPFAR countries, it dropped only 3 percent. And the PEPFAR countries grew three times faster.

Shoring up national securityAmerican military leaders understand that fighting poverty and disease is part of a smart national-security strategy. It was true after World War II, when the United States invented modern development assistance to combat instability in Europe and prevent a third World War, and it’s true today. The more stable poor countries are, the lower the odds that America will need to intervene in them.

More than 120 retired generals and admirals recently wrote a letter to Congress arguing that U.S. aid programs “are critical to preventing conflict and reducing the need to put our men and women in uniform in harm’s way.” While he was the head of U.S. Central Command, overseeing American operations in Syria, Pakistan, Afghanistan, and elsewhere, Secretary of Defense James Mattis said: “If you don’t fully fund the State Department”—which houses many aid programs—“then I need to buy more ammunition.”

Aid is an important part of our broad diplomatic and security relationships. Out of 135 countries that receive some health or development aid from the United States, we have bilateral defense agreements with 131 of them.

These are some of the arguments I have been making in Washington on behalf of American aid. In future posts I will explain how aid not only keeps Americans safe, but also creates jobs in the United States and helps other countries become more self-sufficient. All reasons why I believe this money is well-spent and ought to be maintained.