How would America and Mexico treat a nation more advanced than they are on there border?

I don't think in today's age, an invasion wouldn't happen- not with Mexico at least. I think that there would be many debates over the moon. Judging by the entirely different race, that makes other countries less likely to accept them, so realistically NATO may choose to defend the lunar territory. The US probably wouldn't attack alone for fear of judgement (nor would any other country), but many countries would feel threatened and may choose to act together.