The USSR has been wiped off the map. So has Czechoslovakia, East and West Germany, and Yugoslavia. Before then countries across Africa such as the Gold Coast, Bechuanaland and Tanganyika. Go back further and there was the Austro-Hungarian Empire...the Confederate States of America, the Republic of Texas...

All gone from the maps, together with numerous others. Not one of those countries exists any longer. But the places are still all there, and the same people and their descendants are living there today. None of them needed to be nuked to remove them from the atlas. Apartheid South Africa exists still within the same boundaries, but it is a totally different country, and the old South Africa now seems like a bad dream.