The move away from conventional politics doesn't represent a shift by the electorate towards political extremism, rather a growing frustration at the ruling political class. As Trump said recently, people are tired of "incompetent politicians." The political class may scoff, but it's Trump leading the polls.
We have become a profoundly unequal society. Unless we can build momentum for a new political agenda, we'll be divided into a small minority with fabulous wealth and a permanent underclass with few hopes or prospects. Unfortunately, our mainstream political dialogue shows no sign of adapting to these realities.