Here is how Steve Bannon views the alt-right, answering a question in Europe in 2014 about how to deal with the racist fringe in UKIP and the Front National.
But there’s always elements who turn up at these things, whether it’s militia guys or whatever. Some [of] that are fringe organizations. My point is that over time it all gets kind of washed out, right? People understand what pulls them together, and the people on the margins I think get marginalized more and more.
So Steve Bannon thinks the we should let the fringes be part of the action and have faith that the mainstream populists will push them to the sidelines in the natural to-and-fro of politics.