U.S. Agriculture Secretary Tom Vilsack struck a cautious yet hopeful tone last week regarding U.S.-Mexico bilateral trade relationships, specifically regarding genetically modified corn, following a meeting with Mexican President Andrew Manuel Lopez Obrador Nov. 28.

In a statement after the meeting, Vilsack praised productive dialogue and recommended continued cooperation while also warning that any Mexican ban on genetically modified corn is deeply concerning and would disrupt trade and harm farmers on both sides of the border. “

We must find a way forward soon,...