Spring was a poor season for tourism in Mexico. International air arrivals — the driver of 80% of all tourism revenue in the country, with two out of every three passengers hailing from the U.S. — were down nationwide in March, April and May. That trend continued in June, as spring turned to summer, despite Mexico’s role as a host for the 2026 FIFA World Cup. But outside of the host cities, which received a boost from the event — albeit not to …