Do I need a visa to go to Mexico if I am a USA citizen and have a USA Passport?
Need Mexican Visa To Fly Into Cancun Mexico For A US Green Card & Re-entry Permit Holder?
It is quite obvious that you need a visa to enter Mexico. For that matter you obviously need to get a passport either American or Vietnamese. You should consult the US govt officials because your case is a bit complicated, as you do not want to go to your country back. I am sure that there is a policy for such immigrants. For more info click here.
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