There is a way and, I suggest, only one way to defend populism from a liberal viewpoint: it is to reject the populist concept of “the people.”
Let the people be plural, that is, a collection of individuals. Let each individual be recognized as having a right to veto (at some contractual-constitutional level) any prohibition or mandate he (or she, of course) does not consent to. A fortiori, no subset of the people may use coercion against the individuals in another subset. It follows that the elite or the experts (“they”) or the politicians themselves may not legitimately boss people around. If populism is thus characterized, it is defendable from both a moral and an economic viewpoint as it would coincide with (classical) liberalism. Liberalism is about a negative veto right of each individual–at least as formalized by James Buchanan and Anthony de Jasay, but the paradigm runs deeper. Liberalism certainly and emphatically does not support an unrestricted positive right of some individuals, even a majority of them, to impose bans or mandates on individuals in the plural people.
That is not how populism, in the standard meaning of the word, is defined and sold to the masses, that is, to a majority or a plurality of them. Populism requires the existence of “the people” singular (see, for example, Cass Mudde and Cristóbal Rovira Kaltwasser, Populism: A Very Short Introduction [Oxford University Press, 2017] for the academically accepted definition, which is close to the one I assign to the populists). If “the people” (singular) does not exist as such, then populism is not possible; it is just a label that hides an interventionist, collectivist, and authoritarian ideology. (See my “The Impossibility of Populism,” The Independent Review, Summer 2021.)
To be both internally consistent and compatible with liberalism, populism would have to take “the people” in the plural and liberal sense of “individuals,” with none more deserving of power over his fellows. It would not be “populism” anymore.
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The People in the populist sense, as an organism, by DALL-E
