Why can’t Trump voters be more compassionate towards illegal immigrants?

Excluding the obvious reason that violent and criminal illegal immigrants shouldn’t be allowed to get in, why the seemingly strong hatred towards all illegal immigrants?

As if they are the greatest threat to their existence? Is this all trump voters are capable of, supporting hateful rhetoric and demeaning punitive actions?

Are Americans generally this mean, even cruel that no matter how deplorable their president is as long as he does the job then it’s totally fine?