There are five half-white/half-Mexican NFL players that I know of. Twenty years ago they would considered white, though a bit exotic, like someone with part-Indian ancestry.
But now it's all about highlighting differences and treating Hispanics as another race.
Ask A Mexican.com has an factoid about how immigration has changed. It used to be primarily from the whitest part of Mexico. Mexicans were certainly ethnic, but taking the route to being simply Americans. They married whites, listened to country music and oldies, were allied with whites when fighting blacks. Even now 45% of Mexican-Americans consider themselves white per Census results.
But the pull to be non-white is powerful. There is no advantage to being white. People aren't stupid, they're going to go with the best offer. The 'Mind of Mencia' 'comic' is half-German, half-Hispanic. No mystery as to which way he's going to go.
Part of some master plan? Who knows? It's not good for America, that's for sure.
As far as Spanish is concerned 'White Is Right' may want to check out the 'Why L.A. Sucks' blog and its account of jury duty. Mexicans who revert to an affected accent even though they've probably been in L.A. their entire lives. Kind of the way blacks speak an affected Ebonics to prove just how black they are.
It's not a language issue, it's an identity issue. Croats and Serbs probably put on affected accents too before the breakup.