“The most dangerous scenario,” Gates told Goldberg, “is where something breaks out somewhere else in the world and starts to spread, and then is coming into the United States.” This is where foreign aid becomes essential. The more the country acts on an “America First” doctrine, and the less government money goes into global health, the more threatening that worst-case scenario becomes.

Even though, as Gates said, “we’re less than a third as generous as many of the European countries” in terms of the percent of our national income we spend on foreign aid, the United States is still by far the top contributor to development assistance in terms of sheer dollars spent. Any decrease in the U.S. global-health budget will surely be felt worldwide—and be a danger to national security.

Despite his disagreement with the president’s philosophy, and the fact that his own foundation published a report that found Trump’s proposed budget cuts to global-health spending would result in 800,000 preventable childhood deaths, Gates hasn’t yet given up on cooperating with the White House. “I’m not someone who feels I’m going to refuse to meet with the administration because they’ve done things I disagree with, and not go and talk about things like PEPFAR or malaria or polio,” he said. “I’m gonna go to those meetings and make the case.”

“Being an optimist isn’t saying we don’t need to solve problems,” Gates told Goldberg during their interview. “Being an optimist ... [is] about knowing how life can get better,” he and Melinda wrote in their annual letter. As the CDC faces a looming end to much of its funding that protects the world from pandemics, and the State Department and USAID scramble to fill a funding gap of $8.8 billion, one can understand why, as the philanthropist power couple wrote in their letter, “these days ... optimism seems to be in short supply.”*

It might be true that, as Gates put it in The Atlantic Interview, most people worldwide “wouldn’t want to go back to the 1950s.” But if the next pandemic strikes in a future of decreased funding for medical research, limited health-care coverage, and international discord, it’s possible that some citizens of the globe may find themselves longing to return to a time before “America First.”

Every week, The Atlantic’s editor in chief, Jeffrey Goldberg, talks to someone who is shaping society for the podcast The Atlantic Interview. Subscribe on Apple Podcasts, Stitcher, Google Play, Spotify, or wherever you get your podcasts.

* This article previously misstated the amount of the funding shortfall at the State Department and USAID. We regret the error.

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