Okay fandom. One last chance.
When M. Night cast white protagonists in his adaptation of Avatar: the Last Airbender, a lot of people got angry about that. And when a blonde white girl got cast as Katniss, I got plenty of articles on my dash about how a white Katniss undermines…
Javier Bardem is not Latino, he’s a white European Spaniard, from, in fact, the whitest region of Spain, making him about as Latino as Tom Hardy. Spaniards do not think of themselves as Hispanic or Latino or having the same ethnicity as someone from Colombia, Cuba or Mexico. This is somewhat like telling a British person you consider them the same ethnic group as Jamaicans.
With that out of the way, Hollywood historically has always thought absolutely nothing of casting white people to play Hispanics instead of casting actual Latino actors. The reality is that white actors playing Latinos of any racial makeup is the unquestioned norm in Hollywood. Hell, Al Pacino has made a veritable side career out of it.
I think it must be so easy to rationalize this because white directors and studio execs have a total disconnect from the subtleties of Latino representation in the media, so they think things along the lines of “Some Hispanics look white, or are predominantly of white racial makeup, or could pass for white, so the reverse must be both true and okay! Whew! Glad that’s settled. Get me Tom Hardy on the phone, y’all.” This is absolutely nothing against Tom Hardy as a person, because he’s a good actor, seems like a nice guy and it’s not his fault that he was offered that role. The point is, Hollywood may consider itself post-racial (though it is absolutely not), but they have no concept of being anywhere near post-ethnic, and because Latinos aren’t easily pigeonholed by phenotype or cultural tropes.
So that’s my answer to why Christopher Nolan cast a white British guy as a Hispanic character. Because he could, and because it’s a non-issue to him and everyone associated with the film and everyone he knows, and because that’s what you do when you’re making movies. Anglo actors are the default, even when they shouldn’t be.
Here are some actual Hispanic actors that could have been hired for this role. (I disagree with Danny Trejo - he’s just not the right age, despite being amazing in general.)
Puerto Rican-American David Zayas (“Dexter”)
Cuban-American Danny Pino (“Law and Order: Special Victims Unit”)
Half-Peruvian Benjamin Bratt
My personal favorite choice for the part, Puerto Rican-American Jon Huertas (“Generation Kill” and “Castle”)
Mexican actor-director Gael García Bernal
Puerto Rican/Cuban-American Adam Rodriguez
This is just off the top of my head. These guys are all a) fine as hell, b) the right age range for the role, c) awesome actors and d) actual Latinos. But maybe they were all busy or something, and that’s why Nolan had to cast yet another white actor instead. Who knows.