Lol! You want to go this rout? okay....
Yes, human beings CAN be illegal aliens. If you think the word "alien" is referring to being from another galaxy, then I'll just stop right here and we're done. If you know what the term illegal aliens actually means, good for you. You would then understand that human beings can be illegal and alien to a country they do not belong in.
Illegal aliens did not migrate here. Migration happens legally and without malice. A good portion of illegal aliens MOST CERTAINLY do come here and commit violent crimes. This has been proven already and for you not to know this, you aren't doing your research. Facts: they matter.
You believe Mexico is sending their best here? Really? Drug dealers, drug cartels, murderers, rapists, gang members...that's what the majority of illegals are. Quit hiding under your bed with your fingers in your ears.
Once an "immigrant" crosses the border ILLEGALLY, they have committed a crime. Therefore, they are all criminals. We don't have open borders no matter how often you would like to think so. Try crossing into Mexico illegally and see how long you last there without being severely punished.
I don't really give a damn about the low percentage of illegal aliens coming here to pick apples and cabbage and work construction to send money to their poor families back home. I don't give a damn. You want a better life? Do it legally. This isn't Mexico, as much as you want it to be.