The U.S. appears to be plunging headlong into a new era of isolationism. The White House wants to pull out of international agreements, including the Paris climate deal and the North American Free Trade Agreement. It has issued executive orders trying to halt or slow the flow of refugees and immigrants to the nation.

This is bad for the U.S. and terrible for hundreds of thousands of desperate people across the planet. And it will strangle science. The choke hold will leave us more vulnerable to emerging, deadly viruses and will hamper efforts to explore space and control global threats such as climate change.

Research depends on ideas shared across political borders—including among countries in conflict. Even as the cold war was raging, hostility between the U.S. and the Soviet Union was put aside when American medical researcher Albert B. Sabin and his Soviet counterparts tested a live-virus, oral polio vaccine in the U.S.S.R. That successful trial provided the scientific proof needed for the vaccine's use around the world and ultimately helped to eradicate polio in most countries. During the International Polar Years of 1882–1883 and 1932–1933, nations also put aside their differences to study the Arctic and Antarctic.

Louis Pasteur once declared that “science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world.” Nations have repeatedly seen the wisdom of his words.

The Soviets and Americans also worked together to further space exploration in the 1960s and 1970s—exchanging weather data from and launching new meteorologic satellites and jointly mapping the earth's geomagnetic field. Similarly, when the Soviet Union's Cosmos 936 mission launched in 1977, seven U.S. biological experiments were onboard. And in 2014, before the U.S.'s restoration of diplomatic relations with Cuba was in place, the American Association for the Advancement of Science and the Cuban Academy of Sciences pledged to work together to further research on drug resistance, cancer, emerging and infectious diseases, and the brain.

In recent years the U.S. has taken some crucial steps to strengthen our science diplomacy: In 2009 President Barack Obama spoke in Cairo about working with scientists in the Muslim world to develop novel sources of energy, create green jobs, digitize records, provide clean water and grow new crops. That speech led to the U.S. Science Envoy program, an outreach effort that selects top American scientists to promote the nation's commitment to science, technology and innovation as tools of diplomacy and economic growth abroad. One of the researchers in the program, vaccine scientist Peter Hotez, used his envoy position in the Middle East to create a vaccine research partnership between his American institute and a university in Saudi Arabia.

Yet the future of the envoy program under President Donald Trump remains unclear. Trump's travel bans have thrown researchers' plans into disarray—making foreign scientists and scholars question whether they should attempt to come to the U.S. for jobs or conferences and raising doubts about whether foreign scientists working here can risk visiting relatives in Muslim-majority countries, lest they be prevented from returning.

That is unfortunate because better science—and dialogue about science—benefits us all. Detecting and stopping emerging threats such as Zika or Ebola require partnering with countries around the globe. Understanding the extent of Zika damage and testing candidate vaccines among susceptible populations, for instance, will call for international cooperation.

For space exploration, we need Russia's assistance to ferry our astronauts to the International Space Station. To better map the stars and explore the unknown, we must partner with China because it has the world's largest radio telescope. To help limit the effects of climate change, we need all the big emitters, including the U.S., China and India, to take steps to address the issue and to work toward solutions that will help communities build resiliency.

Let's resist the urge to turn inward and isolate ourselves. Instead we must continue to forge strong ties worldwide, using science as a diplomatic wedge. We gain far more from these partnerships than we risk. Weakening them will hurt us all.