President-elect Donald J. Trump has made a little-noticed vow to impose tariffs of 200 to 500 percent on auto and truck imports from Mexico and recently threatened again to impose tariffs of 25 percent on all imports from Mexico, cancelling out terms of the trade agreement he negotiated with Mexico and touted in his first term. A major concern of his trade advisers is Chinese investment and inputs in vehicles exported from Mexico to the United States.^{[1](https://www.piie.com/blogs/realtime-economics/2024/restricting-imports-mexican-vehicles-will-harm-us-manufacturers#_ftn1)}