Is this the same country that built the Hoover Dam, the Panama Canal, that built the Empire State building in about 14 months? The one that was at nearly zero aircraft produce before WWII and was producing hundreds of thousands of aircraft within 3 years? The one that mounted the Normandy invasion? Is this the country that built the interstate highway system? That put a man on the moon in the span of one decade's effort?
Will someone please tell me what all this nonsense about "we can't build a fence/wall/whatever it takes" to keep our border secure? What the heck is going on here? I know some people disagree, but this is the same weak, "can't do" attitude that is the primary reason (besides politicians) why there aren't two beautiful, reinforced, taller and grander World Trade Center towers standing alongside that awful hole in Manhattan.
I think a big difference is the accomplishments you listed are one thing. Leadership. JFK had a passion for the moon landing, etc. I think if you look back at our greatest accomplishments, it's because whoever was leading the nation at the times led w/passion and we responded in kind. I believe that's what's missing here. Of course we can build a wall along the entire border - if our leadership really wanted to.