I don't have problem with legal immigration. I believe diversity makes our county great. But in order to have national unity there needs to be a shared culture or language at some level. If immigrants don't assimilate and learn the language, history, and customs of the country how do they develop that sense of unity and become Americans. I know it's difficult for older immigrants to learn the english language but their children need to be educated as Americans, not Spanish Americans or Chinese Americans or whatever.
As for the illegal immigrants, as the first word of the phrase indicates they are "illegal". Giving them names like undocumented workers makes it sound like there was some kind of clerical error. They're breaking the law and need to be handled as criminals. I don't care if they're mexicans, cubans, chinese, or canadians. If they're here without government approval, they're illegal.