The Alt-Right is a concept, not an organization. It's all the wingnuts out there that are pretty much living in a world of paranoid delusions, conspiracy theories and who seem to believe that being mean is the solution to everything. Trump largely represents this segment of society.
But another concept that is circulating on the internet is the 'regressive left'. This is all the liberals that buy into any politically correct nonsense that anyone proposes.
For example: the BlackLivesMatter movement seems to take that position that anytime police use force against a black person, the police are wrong. Effectively creating an environment that black people are allowed to commit any crime without fear of police force being used against them. While most of us believe that their are instances that police use unjustifiable and excessive force (not only against blacks, but against anybody that pisses them off), most of us realize that in the VAST MAJORITY of the cases that police use force, the police are JUSTIFIED. Unfortunately, Clinton caters way to much to the 'regressive-left'.
Both the alt-right and the regressive left are idiots, and they are a minority in our society, but they get an inordinate amount of news coverage and control the political dialogue simply because of the sensationalism of their idiotic views.
We need more attention paid to the 'sane middle'.