Which political party (parties) do these thugs support? My experience here in New Zealand is that it is not necessarily a political left will be more internationalist. I know plenty of centre-left or outright leftists in this country that are extremely nationalist.
Hmmm. . . . national socialism perhaps?
No parties out of the "democratic" spectrum. There are the "NPD" (a pure nazi pary), the "DVU" (also nazis but more for the "elderly") and maybe the "Republikaner" (not to mix with the Republicans in the US - also a dumb nationalist and populist party - it is a shame that they can misuse this name).
Personally I would put them into a nice little working camp (no KZ but something "uncomfortable") to give them some reason for their existance again. Leonardo da Vinci said about such people, that all that will be left of them are some filled *hitholes.