Your argument is very confused but I think it is along the lines of "ok, redditcensors says the Berlin Wall is a good analogy because while it was up it was effective, but if they continue the analogy they will see it is no longer up and was removed thus it is not working!" There may also be, though you haven't stated as such that I've seen, an implicit criticism of the analogy in that one wall was built to keep people in and the prospective US wall is to keep people out. Is that an accurate summary of your views? Again, it fails on a number of fronts. The wall was eventually removed when it was determined due to events that border crossing was no longer problematic. And indeed, that may come to pass in the US as well. The original point was that while the wall stood, it was indeed effective at its purpose. It's a simple point that I feel you're deliberately misconstruing. Secondly, analogies are just that, analogies. If they were a precise 1:1 representation we wouldn't need them, we'd just reference the actual thing in discussion. That's why I don't think the keeping people in vs keeping people out portion is relevant, nor any other factors besides the bit about "walls work".