BERLIN, GERMANY - December 20: The Brandenburg Gate (Brandenburger Tor) is illuminated in black, red and gold, the colors of the German Flag to pay tribute to the victims of the attack on a Christmas market in Berlin, Germany on December 20, 2016. At least 12 people were killed and 48 others injured when a truck crashed into a crowded Christmas market in the German capital. (Photo by Maurizio Gambarini/Anadolu Agency/Getty Images)