, I think that there is a lot of unsourced guesswork going on on those sites and there is the possibility that the author was merely making a political commentary. Indeed, as far as walls go, I'd give the world prize to Israel over the folks who have a great wall, for the Israeli wall is not extremely long, but at least you can't simply step over it at random spots. , I got a reality upgrade a few years ago, I retired from the military. Can't get more real than back in the US and living civilian life!  ;)