Horseshoe theory
Etymology
The idea is often attributed to French writer Jean-Pierre Faye and named for the shape of a horseshoe, whose two tips nearly touch. It remains disputed: critics argue it flattens real ideological differences and mistakes surface similarities for deep ones.
noun phrase · /HORS-shoo THEER-ee/
The contested claim that the far left and far right, rather than being opposite ends of a line, curve toward each other and come to resemble one another.
What it names
The observation that political extremes can share tactics and attitudes — distrust of institutions, a taste for authoritarian means — more than they share with the center.
Example
Pointing out that both fringes despised the mainstream press, the columnist invoked horseshoe theory.
Related idea
Horseshoe theory bends the political line into near-contact at the extremes; the conventional left–right spectrum keeps them maximally apart, and critics say the theory commits a false equivalence by treating two unlike movements as the same.