Yep, Texas use to be part of Mexico as every schoolboy knows.
Did you need the "Blue Button" to discover that it is now part of the U.S.A., muffet?
One would hope that the construction workers who build 'The Wall" along the southern border of the U.S. have access to The Milserps Forum and use the "Blue Button" to check whether Texas is currently part of the U.S.A. or Mexico. Otherwise the residents of Texas may find themselves inadvertently annexed to another country.