Everyone hates NAFTA. But what was NAFTA actually supposed to do? Did it deliver on its promise? To understand that, you have to look at America's relationships with two goods: avocados and shoes. Quartz is a digital news outlet dedicated to telling stories at the intersection of the important and the interesting. Visit us at https://qz.com/ to read more. Become a member of Quartz, your exclusive guide to the global economy: http://bit.ly/2E7e7jB