From a liberal perspective, there is only one way to defend populism. It is a rejection of the populist concept of ‘the people’.
Let people be plural, a collection of individuals. Let each individual be recognized as having the right (at some contractual and constitutional levels) to veto any prohibition or order with which he (and of course she) does not agree. Of course, no subset can use coercion against individuals from another subset. Therefore, neither elites, experts (“they”) or politicians themselves can legitimately dominate those around them. If populism is thus characterized, it is consistent with (classical) liberalism and therefore defensible from both moral and economic perspectives. Liberalism is about the negative veto of each individual, at least as formulated by James Buchanan and Anthony de Jasay, but the paradigm goes deeper. Liberalism certainly and emphatically does not support the unrestricted and positive right of some individuals, or even the majority, to impose prohibitions or orders on individuals in the plural.
That is not how populism in the standard sense is defined and sold to the public, to the majority or majority. Populism demands the existence of a “people” singular (e.g. Cass Mudde and Cristóbal Rovira Kaltwasser, Populism: A Very Short Introduction [Oxford University Press, 2017] The academically accepted definition is closer to the definition I assign to populists. Populism is impossible if “the people” (singular) do not exist. It is just a label that hides interventionist, collectivist, and authoritarian ideologies. (my “The Impossibility of Populism,” independent reviewSummer 2021.)
To be internally consistent and compatible with liberalism, populism would have to take “the people” in the plural, liberal sense of “individuals” no longer entitled to power over their fellows. It is no longer ‘populism’.
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