Runes are a family of old Northern European alphabets derived by some unknown route from early forms of the Latin alphabet. There is still some sentimental attachment to them in Northern Europe (particularly in Scandinavia) and the Nazis may in part have used them for that reason. They long predated the Nazis, however.
Like the original Latin alphabet, they were very simple shapes designed to be suitable for carving into stone and wood. The runic "S" has been compared to a lightning flash and that is probably why both the Nazis and the American troops above used it.
"A US Marine sniper team posed with a flag emblazoned with the symbol of the Nazi SS while on duty in Afghanistan, the Pentagon has admitted.
A photograph leaked onto the internet showed the heavily-armed troops crouching in front of the banner as it hung below the American flag.
The lightning symbol, once worn by the unit tasked with the extermination of Europe's Jews, sparked immediate outrage
A spokeswoman said the icon had been used by the troops to identify themselves as scout snipers, a designation unique to the Marine Corps, and was never intended to have Nazi connotations.
In a statement the Corps said: "Certainly, the use of the 'SS runes' is not acceptable and scout snipers have been addressed concerning this issue. 'SS runes' are prohibited from use as a symbol or any other use."