It’s actually rather brilliant.

In an (d)effective 2 party system like ours, running to your extremes has few costs, since the electorate tend to vote parties out rather than vote them in. When the public tires off the ruling party (it helps if you own most of the media) and you do get elected, it’s by:

1. your base that votes for you regardless
2. new voters from the fringe you’ve been courting
3. people who’ve convinced themselves that you’re just pretending to be crazy to court that fringe.

Now you can do whatever you like and if people complain they get shouted down by both sides: “What did you expect? They literally told you they were going to do this.”

In short, it’s how you drag the Overton Window toward that extreme. If only the Left in this country had figured this out years ago, we wouldn’t be saddled with Sir Red Tory.