It's difficult to say exactly how the United States and Mexico would be different if the two countries had gone to war in 1916, as there are many factors that could have influenced the outcome of such a conflict.
However, it's likely that a war between the United States and Mexico would have had significant consequences for both countries. The United States was a much more powerful country than Mexico at the time, with a larger military and a more developed economy. If the United States had gone to war with Mexico, it's possible that the conflict could have resulted in a U.S. victory and the annexation of Mexican territory.
On the other hand, a war with Mexico could have had negative consequences for the United States as well. It's possible that a prolonged conflict could have drained U.S. resources and weakened the country's international standing. Additionally, a war with Mexico could have inflamed anti-American sentiment in Latin America and damaged U.S. relations with other countries in the region.
Overall, it's difficult to say exactly how the United States and Mexico would be different if the two countries had gone to war in 1916, but it's likely that such a conflict would have had significant and lasting consequences for both countries.