Pippa Norris writes: Many American commentators have had trouble understanding the rise of Donald Trump. How could such a figure surge to become the most likely standard-bearer for the GOP – much less have any chance of entering the White House?

But Trump is far from unique. As many commentators have noted, he fits the wave of authoritarian populists whose support has swelled in many Western democracies.

The graph below from ParlGov data illustrates the surge in the share of the vote for populist authoritarian parliamentary parties (defined as rated 8.0 or above by experts on left-right scales) across 34 OECD countries. [Continue reading…]