As the saying goes, “Fences make good neighbors.”
I believe you’re right. Illegal “immigration” invasions will be the cause of WWIII. Too many people still have the brains to cherish their freedom, their cultures and their heritage. Like the native Americans, most Americans still consider our country as being a sovereign nation built on “sacred” ground. If it’s good enough for the Indians, it should be good enough for us.
In the olden days the Rhine held back the Germanic tribes.
Then it froze over.