There is literally abundant fake news, primarily distributed through Facebook. Actual lies. [0] Whether Breitbart is abjectly white nationalist is more debatable, likely by design.

[0] In the practitioners' own words: 1) https://www.buzzfeed.com/craigsilverman/how-macedonia-became... 2) https://www.washingtonpost.com/news/the-intersect/wp/2016/11... 3) https://www.washingtonpost.com/national/for-the-new-yellow-j... 4) http://www.inc.com/tess-townsend/ending-fed-trump-facebook.h...

No. Not two days ago, I listened to a self described white nationalist leader speak at length in his own words. He was not a made up smear, but a real person with real (awful) opinions, who now feels he has kindred spirits at the top of government. So, again, no, "white nationalism" is simply not "mainly a smear used by the MSM".

Breitbart itself describes itself very clearly as a champion for the neo-nazis that have re-branded themselves as "alt-right". Much of the news they provide is clearly misleading.

I wouldn't necessarily go so far as saying Breitbart produces fake news, however there are sites that produce fake news. Completely made up stuff targeting conservatives to make money. This is a very real problem and it needs to be solved.