If you don't have a sense of humor, or are offended by a mexican-american making a joke about other mexicans, then tuff shit.
But that's not what you did.
Now had you said...
A fat Mexican-American and a skinny Mexican-American jump off a cliff, who hits the ground first?
Who cares?
...you might, as a Mexican-American have a point.
I think both the black and the Mexican might think the Mexican-American was not expressing jocular solidarity, hm?
Have you ever been to an American wedding? Where's the vodka? Where's the marinated herring?!-Gogol Bordello