Mexican President Andrés Manuel López Obrador, known as AMLO, has been criticized at home and abroad for his dismissive approach to the global coronavirus wildfire, which is now spreading in his country. But when the smoke clears, Mexicans may find even more fault with his handling of the economy than with his Covid-19 policies.

The evidence suggests that Asia learned from the 2003 SARS outbreak and was somewhat prepared for this virus. Policy makers in Europe, the U.S. and Canada were caught off guard, with inadequate testing...