In Nazi Germany, the swastika (or in German, the Hakenkreuz) became a national symbol.
Poet and nationalist ideologist Guido von List had suggested it as a symbol for all anti-Semitic organizations, and when the National Socialist party was formed in 1919-1920 it adopted it. On Sept. 5, 1935, a black swastika on a white circle on a red background became the national flag of Germany. This use ended in May 1945 with the German surrender.
Americans, and I suspect most Europeans, still accept Hitler's veiw of the swastika as a symbol of hate. Many cultures all over the world have used this shape, and its mirror image; as religious symbols, in decorative paterns, as good luck charms, and various other uses. You often find swastikas that don't have anything to do with racism of any sort. (See swastika for more). But beware of the black on white on red pattern -- that always bodes ill.