Philip Lovas is a former deputy assistant secretary for travel and tourism at the Commerce Department.

In June, I boarded a flight from Dallas to Rome in the initial wave of U.S. tourists headed to Italy following the lifting of pandemic-related quarantines by the Italian government.

The process to enter Italy was simple. Take a coronavirus test before boarding the outbound flight and then be tested at Rome’s Leonardo da Vinci-Fiumicino Airport. Upon arrival, I was tested, received a negative result, collected my checked bags and cleared customs. It took less than an hour, thanks to the fast-moving queues and fully staffed medical center at the airport.

I thought of that trip again last week, when the Biden administration announced that it “will maintain existing travel restrictions” — banning, with few exceptions, visitors from Britain, much of Europe, China, Brazil and many other countries.

The White House blamed the spreading delta covid-19 variant, but infection from it is just as detectable by testing as any other form of the disease. Certainly, the delta variant’s emergence has complicated public health policies around the world this summer, but governments are increasingly recognizing that discouraging international travel is both medically unnecessary and financially unwise.

Britain announced last week that, as of Monday, it would drop its quarantine requirement for fully vaccinated visitors from the United States and European Union. Canada recently announced similar plans.

By restarting international tourism this summer, Spain, Greece, Italy and much of southern Europe were bidding to save jobs and boost economies while New York and other major U.S. destinations continue to struggle for tourism dollars, including from international visitors who fill hotel rooms, restaurants and attractions.

U.S. officials should realize, as these governments have, that travel restrictions that might have been introduced 17 months ago don’t make as much sense as they once did. The covid-19 vaccines are effective, testing is widespread and the medical community knows much better how to treat infections.

The U.S. government already requires Americans returning from other countries to provide a negative coronavirus test result. Enhancing safety protocols for international travelers by requiring evidence of vaccination or a negative test result would require relatively little work to implement.

The state of Hawaii already runs an effective covid-19 testing operation from the U.S mainland, including pre-clearance of passengers who’ve provided necessary testing and vaccination documents at departure airports. A responsible return to normalcy in international travel could play a significant role in the global economic recovery.

It would certainly boost the U.S. economy. In 2019, the country ranked first in the world in tourism receipts, according to the World Tourism Organization, with $214 billion — more than double those of Spain, the next closest country. The United States ranked third in the number of international visitors in 2019, behind only France and Spain, which draw a sizable portion of their tourists from cross-border visitation in Europe.

As other countries relax their restrictions on international visitors, billions of dollars that could have been headed to the United States are instead being redirected overseas. That holds short- and long-term ramifications for U.S. tourism.

Before the pandemic shut down international travel, the average overseas tourist in this country spent $4,200 and stayed for 18 nights. Fewer tourists coming runs the risk of fewer tourists returning: If the U.S. borders remain shut through the end of 2021, that means nearly two years of international travelers’ finding new and potentially preferred options to the United States.

Restarting international tourism to the United States is not just an economic issue but a diplomatic concern as well. I have heard many times from members of the State Department that the soft diplomacy of international tourists visiting the United States makes their job easier. Every traveler who comes to this country and has a good experience takes those feelings home and conveys them to friends and family, buttressing the United States’ image abroad.

The least the United States can do is reciprocate when countries such as Italy, Canada and Britain relax their rules regarding U.S. travelers. Better yet, open the United States to the world again by allowing any fully vaccinated visitor who poses no security threat to enter the country and enjoy its offerings.