<human>:  How did the US-Mexico border disputes evolve since the 19th century?
<bot>: Since the 19th century, the US-Mexico border dispute has evolved greatly. In the mid-1800's, both countries had territorial disputes as the United States sought to acquire more land in Mexico in what happened to be known as the Mexican-American War. This eventually resulted in the 1848 Treaty of Guadalupe-Hidalgo, which established the US-Mexico border along the Rio Grande and the Gila River, and Mexico ceded much of its land to the United States, including the modern-day states of California and New Mexico. Since then, the US-Mexico border dispute has primarily been focused on immigration and trade, with the United States passing more restrictive immigration laws and tariffs, as well as building a wall along the US-Mexico border to deter illegal immigration and smuggling. The US-Mexico border dispute is ongoing and continues to evolve as both countries negotiate different policies and practices.