Surely there’s no one who supports their presence in the West other than the leftists who hate the white race and Western civilization.
Leftist thinking will have to be rooted out and destroyed. If “Nazis” can be marginalized, so can leftists. A good place to start is for American state legislatures to defund radical university administrators and professors.
As to Europe, you have to find your own nationalist politicians and elect them to high offices. Better yet, just throw the violent, revolutionary left into prison and let them rot.