There are some important lessons to be learned here. History is repeating itself but in reverse. Now it's Mexico trying to take Texas for it's selfish reasons and this country doesn't even ask that the settlers be of good moral character, abide by US laws, or ever become US citizens.
Mexico was too weak of a country to control it's northern territories and it couldn't convince Mexicans to move into those regions to build them up. The deal was made with Spain in the first place, then there was the Mexican War of Independence from Spain, the northern territories that included Texas were only Mexico's for about 25 years, their claim on them isn't based on much.
This is true, but we possibly need to look at other dynamics of the indigenous peoples that were living in the area at the time, like the Tarumara Indians, the Apaches and all that . . . various tribes had lived there for thousands of years. Some of the so called Mexicans were not Mexicans at all, but native Indians who lived between what we know now as U. S. and Mexico. ( Remember the Apaches us to migrate deep into Mexico, and vis a verse). When the line was drawn by the U. S. at the Rio Grande, one perhaps should remember that many of these people had been living in the land they inherited by there forefathers. This means their families have lived there for thousands of years. It is very natural for Spanish Indian, French Indian, Irish Indian to be in the area. (Sort of like the Palestinian situation). Yet their population was low. Today, it's very natural for these individuals to speak Spanish. It's very natural for many of them to have dark skin, appear to look Indian and all that . . . . it's very natural that many of their families still live in the same area. It was once their homeland.
Fewer than that, actually. It was only about 13 years, and there were many more Anglos than Mexicans in Texas.
Those who now whine that the Texans stole land that their Mexican ancestors had lived on for hundreds of years simply do not know their history.