A combination of a triple-parallel wall and a close re-examination of laws that draw illegal aliens here would definitely be effective and help American Citizens. As WELL as would-be immigrants. (as opposed to ILLEGAL ALIENS).
Mongolia is part of China now. And I see what you mean about a wall could not stop people today. I mean the drug cartels have more money than France and France built a tunnel from France to China that could be paid for with one day of drug shipments but Maybe the Mexicans could be persuaded to become a State in the USA.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.