US troops are seen installing concertina wire in Nogales, Ariz., days after the Pentagon said it will deploy an additional 3,750 troops to the Mexico border. https://nbcnews.to/2MPGSTe | NBC News

On 15 August 1961, 19-year-old East German border guard Hans Konrad Schumann was sent to the corner of Ruppiner Strasse and Bernauer Strasse to guard the Berlin Wall on its third day of construction. At that time and place, the wall was only a single coil of concertina wire. Throughout the day, as Schumann paced ten steps up and down, West Berlin residents shouted catcalls: “You pigs!” “You traitors!” “You concentration camp guards!” One scene particularly upset Schumann. A young lady in East Be