> That is certainly true, and the downsides of a two-party system are not small. On the other hand, multi-party systems have a tendency to build less stable governments, which was one of the reasons for the downfall of the Weimacher Republik and the rise of the NSDAP.

I'm no longer convinced that this is a good argument, given that a two-party system just gave rise to the Trump party over the past four years - and it was 'rejected' by a mere ~60,000 votes in a country of 350 million.