Actually, it is a modified Othala which is symbolic of Odin and calls to bloodline, ancestors, inheritance... Ancient property. it's modification is likely Enochian, likely a binding, though beyond my ready knowledge... But certainly an occult sygil... And whether 'nazi' or not is the least of your worries. It is an Elder Futhark rune. It is old magic.
And with a modicum of knowledge, one would be truly astonished at what is laid out right before your unbelieving eyes, everywhere, and every day.
It was placed there deliberately, though likely unknown to ignorant Christian Republicans.