But if we take away the freedom to "allow these girls to promote racisim and hate by singing these kinds of songs and sporting swastikas in public" we've begun our descent down the slippery slope.

Who decides what written words, songs, sayings, etc. do or don't promote racism?

And don't people have the right to be racist if they choose to, and to promote racism if they wish to?

And isn't the Nazi Party a political party? Surely you're not suggesting that we start selectively banning certain political parties with whom we don't agree, are you?

(You knew I was gonna say this, didn't you? :p )