"the reason Mexico lost Texas: they trusted all those gabacho settlers."
They obviously receive there information from Chicano Studies, such as those taught here at the University of Dayton. The only problem is that it is an incomplete and poorly interpreted history to demonize the USA and "white" American Citizens. They fail to realize what lead up to the Texas Disillusionment.
Texians had become increasingly disillusioned with the Mexican government. Many Mexican soldiers garrisoned in Texas were convicted criminals who had been given the choice of prison or serving in the army in Texas. Many Texians were also unhappy with the location of their state capital, which moved periodically between Saltillo and Monclova, both of which were in southern Coahuila, some 500 miles (800 km) away; they wanted Texas to be a separate state from Coahuila (but not independent from Mexico) and to have its own capital. They believed a closer capital would help to stem corruption and facilitate other matters of government.And then you have Santa Ana's contributions to the problem as well:
The Constitution of 1824 that was no longer being recognized by General Antonio López de Santa Anna Pérez de Lebrón who decided to abolish the Constitution of 1824 and proclaimed a new anti-federalist constitution in its place, the Siete Leyes of 1835.
Between 1829 and 1832, a series of Mexican presidents were killed in a series of coups. Santa Anna had a hand in each of these events. The Mexican Republic became heavily divided between two factions known as Conservatives, who were for a centralized monarchical government, and Liberals, who were for a democratic federal government. In the presidential elections of 1833, Santa Anna ran as a liberal and won. Soon after, Santa Anna retired to his hacienda, allowing Vice President Valentín Gómez Farías to run the country. The government initiated drastic liberal reforms, angering the Conservatives. Returning from his hacienda, Santa Anna renounced the government's policies and overthrew the presidency, forcing Gomez Farías and many of his supporters to flee Mexico for the United States. Santa Anna declared that Mexico was not ready for democracy, became an openly Conservative centralist, and appointed himself dictator. The War of Mexican Independence started after Napoleon invaded Spain in 1808, now Santa Anna fancied himself, the Napoleon of Mexico.
At the same time Texas declared independence, other Mexican states also decided to secede from Mexico and form their own republics. The state of Yucatán formed the Republic of Yucatán, which was recognized by Great Britain, and the states of Coahuila, Nuevo León, and Tamaulipas joined together to form the Republic of the Rio Grande. Several other states also went into open rebellion, including San Luis Potosí, Querétaro, Durango, Guanajuato, Michoacán, Jalisco and Zacatecas. All were upset with Santa Anna abolishing the 1824 Constitution, disbanding Congress, changing the structure of government from a federal structure to a centralized one, and the expulsion of the Spaniards. Texas, however, was the only territory to be successful in detaching itself from Mexico.
So, after the missing information left out by those that blame the "white man" for their own ethnic strife, where is it that the USA or the "white man" stole Mexican land, i.e. Texas from Mexico??