A naturalized US citizen renounces all other allegiance. Mexico may claim him, but the individual's later decision is controlling.
"Natural Born Citizen" is a question of fact that aims to limit the pool of individuals eligible to the obtain the office of president, by probing the "accident" of birth. That Congress accepts a dual citizen at birth (again, naturalized citizens are often MORE patriotic that those raised by citizen parents) as meeting the constitutional eligibility qualification is a travesty.
When Romney was born, Mexican laws did recognize children born to alien fathers as Mexican citizens, they were recognized as aliens and citizens of the father’s country. Romney never held any other allegiance but to the United States.
100% agree that naturalized citizens are often more patriotic than natural born. The latter have no point of reference against which to measure all that they are given at birth. Those who left their homeland and went thru the process of naturalization have a far greater appreciation of this country,
My daughter’s new father in law immigrated to the US as a young man, fulfilling his life’s dream. At his son’s and my daughter’s engagement party, coincidentally on 7/4 last year, he gave the most beautiful toast reminding the guests about what this country is and why it IS exceptional. Almost brought me to tears. He’s not eligible to be POTUS, nor as I understand it, is my son in law who was born in the US with dual citizenship. Would they serve well? You bet. But they are not eligible. It’s as simple as that. And, I dare say, they respect this country too much to even consider trashing its Constitution. I’m just glad they are both on these shores.