History tells us, that only works in shortest of terms. If anything it raises their anti-establishment reputation (see how NDSAP was banned and it did nothing to stop Hitler's rise).
EU and Germany's woes won't go away with banning a party. You can't have a single currency without a joint fiscal policy (aka federal state).
The lesson the US should have taken from that period in Germany is that if a party leader attempts a coup once, you should not let them and their party get elected to finish the job.
What? The opposite is true. It was treating Hitler with kid gloves that enabled his takeover.
You definitely can, and should.
Letting bigots and racists continue to express these views is extremely problematic.