As much as "changing" the name is stupid, Google isn't here to pick battles between countries.
Quick check shows that google.com.mx shows it always as "Gulfo de Mexico". That's all that matters.
Quick check shows that google.com.mx shows it always as "Gulfo de Mexico". That's all that matters.
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I don't know why they decided to to do that in Canada. In the UK (for example), it only says "Gulf of America", same with Germany.