I guess you don't have a fence around your back yard.
I do. It helps deter criminals, and keeps stray kids from drowning in my swimming pool.
Thus you would keep your forefathers out. You probably lock your doors too. I don't, nor do I have fences. Strangely I am not overwhelmed by criminals and children with a death wish.
Without control of our border, America will gradually sink into an average country, instead of leading the world towards a desired goal.
The problem is not people who want to work and contribute to that America.
It is the nature man and socialization.
We gather in neighborhoods and we like to hoard things.
People who crave power will always dominate the meek.
It is the nature of
selfish people. You must include yourself, if you make this a blanket statement.
You still did not answer the question though -- what gives you the
right to draw lines? Your accident of birth is not a right. Having a "power" to drive off others is not a right.
Try thinking beyond your nose.
Enjoy.