The North American Free Trade Agreement, or NAFTA for short, went into effect in 1994. After it’d been passed, Mexico tried to export their avocados to the U.S. and the U.S. government resisted. The government claimed that fruit flies would enter with the avocados and destroy California crops.
The Mexican government invited USDA inspectors to come to Mexico and check for themselves, but the U.S. government declined. So, the Mexican government countered with offering to only sell their avocados to the northeastern U.S. states in the winter, because fruit flies can’t withstand that level of cold.
The U.S. government drew back again, but ended up complying when Mexico started setting up barriers for purchasing U.S. corn. Today, Mexican avocados are allowed in all 50 U.S. states, only because USDA inspectors eventually did go down and check millions of fruit and found no problems. Today, Chile, Peru, and Mexico import avocados to the U.S.