Which State of USA were once part of Mexico?

Question

What is the name of the cooperation between the USA and Mexico and countries of Central America, with the aim of combating the threats of drug trafficking, transnational organized crime and money laundering?

Answer 1

Texas, Arizona, New Mexico, Colorado, Utah, and California.
The Mexican Cession consisted of present-day U.S. states of California, Nevada, Utah, most of Arizona, about half of New Mexico, about a quarter of Colorado, and a small section of Wyoming. See the attached image for more detail -

Now lets go into the history of Mexico-USA: Texas, decided to become independent in 1836, Mexico decided to fight back and the Texas War began. After winning the war with the help of the United States they become the Texas Republic for a few years before uniting with the United States, event that boosted Mexico to make another war with USA in 1847.

After the war, United States, through the Guadalupe Hidalgo treaty, “bought” Mexico at a very cheap price (15 million dollars) the states of California, Arizona, Utah, Colorado and New Mexico. Later they got La Mesilla a small territory between Texas and Chihuahua and finally USA returned Mexico the very small territory called El Chamizal in 1964.