And intelligent people with good verbal skills discuss those important purposes, they don't simply say "the law is the law is the law, what don't you understand about illegal."
Most people like President Bush who have delt with the problems and "important purpose behind" the immigration laws for years have concluded that the immigration laws are not working correctly and need to be reformed to reflect reality.
The laws are going to be changed. When they are will you still say "the law is the law" and support the new laws as fully as you support the current ones? You can't have it both ways if you are a strict legalist.
Sure, as long as the new immigration laws don't include giving amnesty to illegal alien lawbreakers. If they do, Americans will protest against those laws, like they do against any law they dislike or that they feel is unfair, unethical, or immoral in some way.