The walls around socialist countries are to keep the people in not those willing to come out.
People flee to freedom not into slavery.
The point is that we have control over our population growth that has nothing to do with birth control or infringing the liberties of Americans. Since 1970 our population has increased by 100 million and we will increase another 135 million within the next 40 years. This is like moving the combined populations of Mexico and Canada to the US. 75% of our population increase comes from immigration.