I saw a lecture by Dr David Starky recently where he gave an interesting insight about populism. it was essentially that democracy used to mean the will of the majority but with the post war consensus and the civil rights movement it changed to the will of the minorities. That's why populism became the new word for will of the majority. 

 Democracy is mathematically impossible.  Not kidding:

https://www.youtube.com/watch?v=qf7ws2DF-zk

Its always the rule of the minority.  

 I'm wasn't really advocating for democracy btw, just thought it was an interesting take on why the word populism was needed at all