The original immigrants assimilate the least, the next generation is virtually indistinguishable from other Americans and by the third generation they are fully assimilated.....
this tells me right here that you dont live around these folks....you are exhibiting the attitude im talking about ....we have Mexicans living here for up to 20 years that know very little English.....we have Mexicans here that can speak English but talk to their kids in Spanish and so their kids know very little English by the time they have to go to school .....we have Mexican kids here who are born here but speak English like they are just learning it....and they are in Jr High.....we have Mexicans here who are very content to live in their own little enclaves and this includes many of their kids....because of people with your attitude....and please dont tell me im full a shit i have lived in a neighborhood that is 70% Mexican and MANY of them are Illegals for 45 years....your little fantasy about the 3rd generation only works if someone if "pressuring" someone to assimilate...and i worked with quite a few Mexicans who were born here who will tell you this too,one of the reasons many of them are harder on the Illegals than other people are....
Your personal anecdotes are irrelevant.
Please provide hard statistical data establishing that assimilation fails unless it is "pressured".
Oh, and FYI, I live in a community that is highly diverse too (whites were less than 50% at the time of the 2010 Census) and assimilation is happening just fine without the need for any "pressure". If there is any "pressure" it is only coming from the immigrant parents onto their own children to do well so that they can make a better life for themselves than their parents were able to afford.
But that too is irrelevant.
Only the data counts so let's see what you have.