The horseshoe theory is a venerable idea about how political ideas work. The gist is that at the endpoints of the ideological spectrum, you start to find similarities. The spectrum “bends” like a horseshoe and the far left and far right suddenly look kind of alike – and maybe more similar to each other than they are to those in the political center.
One example comes from a 1985 article by political scientists Herbert McClosky and Dennis Chong, “Similarities and Differences Between Left-Wing and Right-Wing Radicals.” They summarize the similarities like this:
Nevertheless, while the two camps embrace different programmatic beliefs, both are deeply estranged from certain features of American society and highly critical of what they perceive as the spiritual and moral degeneration of American institutions. Both view American society as dominated by conspiratorial forces that are working to defeat their respective ideological aims.
The degree of their alienation is intensified by the zealous and unyielding manner in which they hold their beliefs. Both camps possess an inflexible psychological and political style characterized by the tendency to view social and political affairs in crude, unambiguous and stereotypical terms. They see political life as a conflict between ‘us’ and ‘them’, a struggle between good and evil played out on a battleground where compromise amounts to capitulation and the goal is total victory.
It’s remarkable how fresh that sounds, despite being published 40 years ago.
Here’s a new example – with a twist
A brand-new example comes from an article by Eduardo Ryô Tamaki and Yujin J. Jung, “The non-linearity between populist attitudes and ideological extremism.” What they find is the same horseshoe: Populist attitudes are more prevalent on the far left and far right. (But there’s a twist!)
Why would we expect populist attitudes to be more prevalent at the ideological extremes? First, let’s define populism. Tamaki and Jung, building on other work, define it as “a thin-centered ideology that divides society into two homogeneous and antagonistic groups – ‘the pure people’ and ‘the corrupt elite’ – and argues for politics to be an expression of the general will of the people.”
The ideological extremes are thus expected to be more populist because of certain cognitive tendencies. The far left and far right often share an “us vs. them” view of the world – even if they define “us” and “them” differently. Both groups also tend to oversimplify the world, and hold on to their simplified views with confidence. They are cognitively “rigid.” And they are particularly hostile toward those they view as opponents.
On top of that, the far left and far right are both “people-centered” in their way. They distrust authorities and “elites.” Thus, they valorize “ordinary people” as the only reliable and worthy decision-makers.
What’s the evidence?
Tamaki and Jung use survey data collected in 43 countries between 2016-2021. They measure populism with these questions:
- What people call compromise in politics is really just selling out on one’s principles
- Most politicians do not care about the people
- Politicians are the main problem in [country]
- Most politicians only care about the interests of the rich and powerful
- The people, and not politicians, should make our most important policy decisions
They combine those questions into a scale. They then compare populism scores to how liberal or conservative people are, relative to the average in their country. The resulting graph looks like this:
Not a perfect horseshoe, of course, but the higher populism on the ideological extremes is clear.
Now, you might be thinking, what’s going on with that hump in the middle? Tamaki and Jung note that it’s a group of people who pay little attention to politics and position themselves in the center in the absence of concrete policy preferences or any true ideological moderation. If you take out the people who put themselves in the center but also say they don’t pay any attention to politics, you get something even more like a horseshoe:
The twist
The twist is that the exact shape of the horseshoe depends on the party system in a country. For example, if populist ideas are concentrated in far-right parties, then the horseshoe is lopsided, with more populism among far-right voters. And so if you look across different party systems, you get this:
The top row confirms the pattern: More populism on the right in systems with more prominent right-wing populist parties, and more populism on the left in systems with more prominent left-wing populist parties. In short, populism is a horseshoe, but context matters, too. To be clear, this is a descriptive exercise. The argument is not necessarily that ideological extremism “causes” populism. But the descriptive pattern still tells us a lot about how populism works in real-life politics, and why it sometimes makes for strange bedfellows.
