This image ran in Mexico as part of an advertising campaign for Swedish (?) Vodka company, Absolut. The picture is a map from the 1830s, when much of what is now the southwestern United States belonged to Mexico. As you can probably figure out without me needing to tell you, the ad caused an uproar among many groups in the anti-migrant movement, as well as among many Americans who aren't connected to said groups but who have heard about the vast Aztlan conspiracy from news media and other sources. Hell, the success of an advertising campaign with a map of historical Mexico including about half of the US is probably the best support for the existence of an Aztlan conspiracy yet. There are two things that some people forget, though:
1. Absolut Vodka is extremely tasty, and Mexicans (and anybody else) would buy it even if it had an ad campaign showing Mexico being admitted to the U.S. as the 51st state, and
2. It really ain't that serious.
I've heard comments from Mexican immigrant friends and family members which, if taken out of context might appear to non-Mexicans to be hostile, entitled, Aztlanian (new word), or whatever you want to term it. Jokes about Mexicans taking back the Southwest "one baby at a time", for example. Jokes like these are made pretty frequently among Mexican immigrants, and I'm guessing in Mexico itself, as well, which is probably why a campaign like this would go over well.
I think these jokes might be more easily understood by people from Texas, or even just people from the south in general. Texans, unless they're self-hating wannabe New Yorkers (I used to be one of those and have since seen the light), tend to be very proud of being from Texas, even if they live in the city and their eyes glaze at the first note of a country song. We have similar jokes that are pretty common here, like threatening to secede or pointing out that we can go back to being the Republic of Texas pretty damn fast anytime one of those other states starts getting uppity. Would we ever actually consider seceding? Hell no. We like being part of the US, but we also like that there's a part of our history that sets us apart from it.
Ads tend to be funny, or at least try to. Just because some Mexicans might raise their glasses and say "hell yeah" with a mischevious gleam in their eye to Absolut's ad, doesn't mean that they want to take up arms and reclaim what's Alta California. Undocumented Mexicans have more important things to worry about than the Alamo, and remittances aren't some kind of sneaky rendition of the Treaty of Guadalupe Hidalgo. Now can we all just sit back and have a shot of Vodka without worrying about some overblown conspiracy that, let's face it, we can't even pronounce?

Hell yeah, Spring Branch! I used to live there.