Populism isn't a political ideology but a critique of institutional democracy. It starts with Rousseau's idea of the general will but seeks to express this through the conventional route of elections and popular votes rather than insurrection. Hillary Clinton's mistake in describing Donald Trump's supporters as a "basket of deplorables" was to characterise an orthodox political movement using language normally reserved for the mob. Though destabilising to bourgeois parties, populism has always been an impeccably liberal cause whose rhetorical style originates in the eighteenth century critique of court politics and factions. Even today we still see a concern with monarchical legitimacy (Obama's birth certificate), the influence of unelected eminence grises (Goldman Sachs alumni), and the role of beholden minorities (we too easily forget that well into the nineteenth century many liberals characterised Jews as an impediment to progress and the forging of national identity precisely because they were seen as compromised servants of the ancien regime).
Though fundamentally liberal, populism borrows a critique of virtue from Burkean conservatism. It believes that established parties or representatives have been corrupted by cynical elites and have thereby betrayed the people. Betrayal is central to populism, which is a clue as to its nature: it seeks a restoration, not a revolution (you can see this in the populist horror at the Tory government's blithe dismissal of parliamentary sovereignty, which we supposedly re-established in June through a popular vote). In many ways populism is the revenge of the theory of liberal democracy on its practice. During the age of restricted franchises, when "the people" represented a relatively privileged community that excluded much of the population, populism was essentially bleeding-edge democracy and thus dismissed as an irresponsible enthusiasm that jeopardised cautious liberal progress (you can still hear echoes of this gradualism in the PLP criticism of Jeremy Corbyn).
With the move towards near-universal suffrage in the late nineteenth century, and the need to protect political and economic interests from majoritarianism, liberalism began to downgrade the general will in favour of pluralism, often justified on utilitarian grounds by thinkers such as John Stuart Mill. The institutional expression of this was a growing emphasis on "civil society" as a collection of autonomous organisations, from progressive charities through trade unions, rather than just the market-oriented "system of needs" theorised by Hegel and Marx. This in turn leads to the liberal redefinition of populism as a narrower critique of establishment politics and in particular the institution of parties (first in the US after the Civil War and then in Europe after WW1). While this populist critique could lead to plebiscitary dictatorship, it also remained a respectable strand of thought among centrist and conservative authoritarians. De Gaulle and Hitler could both be plausibly described as populist in their appeals to the nation over the heads of "sectional" parties.
The term became increasingly pejorative in Europe after WW2 as the concept of "the people" was institutionally absorbed by the state through social democracy. To call yourself populist, or the people's party, was seen to be presumptuous and to have distasteful echoes of the nationalism of the 1930s. This shift was reinforced by the presentation of loaded terms like "popular" and "people", employed by communist regimes and Third World insurgencies, as in opposition to the "freedom" of liberal democracy. Across the West, "the people" were rhetorically marginalised in favour of "ordinary people" or (in the US) "the middle class". After 1989 and the eclipse of the populist left, the shift of the political centre to the right caused populism to be increasingly identified with xenophobia. This was not because it had become (or always was) racist, but because much of its anti-elite language had been adopted wholesale by mainstream parties ("shrink the state", "hardworking families" etc.), requiring the definition of populism to shift ever further to the right.
In other words, populism is a flexible term employed by liberals to defend the political establishment. The recent flurry of books and op-eds on the subject reflects a desire to dialectically redefine the centre by filling the populist "basket" with as many negatives as possible: racist, bitter, ignorant, misogynistic. But defining liberalism in opposition to populism is not only risky, as Brexit has shown, it doesn't address the philosophical vacuum revealed in 2008. John B Judis's The Populist Explosion, is typical of the genre in avoiding the question implicit in populism: who is liberalism for, if not the people? In a summary in The Guardian (where else), he starts by defining populism's instrumental flexibility as inherent to the subject rather than its critics: "There is no set of features that exclusively defines movements, parties, and people that are called 'populist'". This is contradicted by his thinkpiece's own introduction: "populism is a style of politics that pits 'the people' against 'the establishment'", which is a definition accepted by most political scientists and historians. Populism assumes a people with a common interest and an elite with a contrary interest. That much is obvious.
Since 2008, the political centre has faced a popular challenge from the left, as the marginal anti-capitalist rhetoric of the 90s has gained purchase, as well as from the right. While some liberals have attempted to tar the left with populism's nastier habits, e.g. the desperate search for antisemites in the Labour Party, Judis prefers a more categorical (and pluralistic) approach: "Leftwing populists champion the people against an elite or an establishment. Theirs is a vertical politics of the bottom and middle, arrayed against the top. Rightwing populists champion the people against an elite that they accuse of favouring a third group, which can consist, for instance, of immigrants, Islamists, or African American militants. Rightwing populism is triadic: it looks upward, but also down upon an out group." The characterisation of right populism as a movement that always seeks an enemy within is misleading. While "in-group" political formations, such as nationalists or racists, employ populist tropes - notably the twin ideas of a homogeneous people and a traitorous elite - not all right-populists are programmatically bigoted.
In fact, a better description of right populism is that it represents a naive view of capitalism: a belief that hard work will be rewarded but that the competition is being rigged by "vested interests". While some right-populist movements do reflect the fear of the déclassé (a phenomenon in developing nations as well as developed ones), what unifies them is the "just desserts" ideology central to liberalism. Examples of centrist or centre-right populist movements that did/do not make a fetish of an "out-group" would be Ross Perot's Reform Party in the US and Beppe Grillo's M5S in Italy. These parties tend to arise when the political system is seen to be failing, but their commitment to institutional reform and public virtue is indicative of their essentially conservative and restorative temperament. The liberal insistence that a scapegoat is the sine qua non of right populism is a way of diverting attention from an often coherent critique of the establishment in its own terms - i.e. the denial of opportunity, the lack of fairness, the poor rewards to obedience. What triggers right-populism tends to be rich bankers being bailed out and spared jail sentences, not the continuing influence of the Rothschild family.
Left populism is a critique of a system, rather than a judgement on the ethical failings of a particular group of people. Consequently, the traditional liberal response has been to accuse it of impossibilism, of making "demands that the populists believe the establishment will be unwilling to grant them". Judis sees Greece as a good example of this: "If they are granted in whole or even in part, or if populists abandon them as too ambitious – as Syriza did with its demands for renegotiation of Greece’s debt – then the populist movement is likely to dissipate or to morph into a normal political party or candidacy". This ignores that Syriza was a normal political party, founded well before the euro-crisis and committed to parliamentary democracy. It also ignores that the party's key proposal for the write-off of Greek debt, which led to its electoral success, was both feasible and accepted by many centrist politicians. The "impossibility" was the EU's determination to protect French and German banks through the imposition of punitive bailout terms.
Judis's interpretation of Syriza's trajectory highlights the liberal belief that populism is a temporary condition, an aberration rather than a permanent interest. As a result, it is often described by medical analogy: a virus, rapid contagion, feverish crisis, recovery. The idea of the people as a sick body that must be cured is little advance on Plato's characterisation of the demos as a "beast", or Aristotle's characterisation of it as a "child". What this attitude doesn't do is acknowledge any plurality among the people, because populism and pluralism are antagonistic in liberal thought, hence the importance of self-ascribed homogeneity in the definition of the former. In fact, the evidence is that populist movements are unstable and fissiparous - i.e. heterogeneous and plural - which is why they often follow a trajectory of rise and fall. Syriza is the "coalition of the radical left", and has consequently been riven by defections and protests after its "historic compromise", while the current meltdown of UKIP suggests that the populist right is no more stable and that victory may be the most damaging development of all. Liberals explain this contradiction away by suggesting the homogeneity is false consciousness, hence the emphasis on "facts" that disprove populist claims and anecdotes about those who eventually "see the light".
Writing for an American audience, Judis claims that modern populism owes its template to the People's Party of the 1890s, a democratic insurgency of small farmers and those who felt they were being disadvantaged by big business. The historiography of the People's Party has oscillated over the years between a view that they were essentially reactionaries resisting industrial progress and egalitarians protesting at monopoly and inequality. Judis leans more towards the former school, whose leading light in the 1950s was Richard Hofstadter. As a result, he fails (at least in his Guardian summary) to mention the movement's influence on the Democrats, via William Jennings Bryan (who enjoyed a brief revival recently as an explanatory model for Bernie Sanders), and the Progressive Era more generally. Instead he cites George Wallace and the instrumental use of racial bigotry in the 1960s as the quintessential form of modern populism, inheriting the rhetorical style of the 1890s and providing a bridge to Donald Trump.
A more telling omission - significant given the seminal role of Hofstadter as the author of The Paranoid Style in American Politics - is the instrumental use of populist rhetoric and tactics in post-war anti-communism, which famously produced the "excess" of Joe McCarthy's campaign against the secret elite of communists and homosexuals supposedly embedded within the State Department. The Italian political scientist Marco D'Eramo makes the crucial point that in the postwar era, "populism was perfect for constructing a bridge linking communism and fascism" and that "as a 'utopia of the past', it connected the historic threat of fascism with the looming, future menace of communism". The McCarthyite frenzy was a small price to pay for this useful equivalence. One byproduct of this process was the idea that populism was antithetical to human rights, which has led to modern liberal attacks on its lack of virtue (Trump's misogyny) being more effective than attacks on its lack of plurality (some women still support Trump).
Given its importance to anticommunism, it should therefore come as no surprise that populism underwent a further mutation after 1989. While the succeeding era was one in which many countries "joined the West", in the form of NATO, the EU or the WTO, these moves were offset by leaving the Warsaw Pact and the nonaligned movement. What wasn't apparent in a triumphant West was that many of these acts of joining were more qualified than the acts of leaving. For example, it is now clear that many East Europeans thought they were signing up for economic "freedoms" but not social reform. In net terms, the world actually became less cohesive as the old blocs either evaporated or were diluted by sheer numbers. A paradox of globalisation is that increased economic integration was parallelled by greater political disintegration, of which Brexit and Syria are recent examples.
Though liberals like Judis have been quick to point the finger at 2008 (or even the rise of social media), the populist upsurge in Europe starts two decades earlier with the electoral advance of the Front National in France (the FN are Fascist, but they employ right-populist rhetoric), which provided a template for reactionary parties across Europe after the Berlin Wall came down.
The current "wave of populist insurgencies" is notable for the broad acknowledgement that the elite against which it is arrayed is globalised: multinationals, Internet businesses and "liberal cosmopolitans". This provides obvious scope for xenophobia - the twin claims that domestic elites owe a greater loyalty to fellow cosmopolitans and that natives are being dispossessed by immigrants - but the essence of the protest is that the institutions of democracy, and civil society more broadly, have failed to adequately respond to globalisation (the recognition of this partly explains the political centre's revived interest in Karl Polanyi and his idea of the "double movement"). For example, the existential debate over the EU concerns whether it is part of the problem or part of the solution. Predictably, starry-eyed liberals like Timothy Garton Ash reckon that "To remedy the unintended consequences of globalisation we need more liberal internationalism, not less" (don't you just love that "unintended"?)
More thoughtful liberal analysts take a subtler position. As Cas Mudde puts it, "populism is an illiberal democratic response to undemocratic liberalism. It criticises the exclusion of important issues from the political agenda by the elites and calls for their re-politicisation. However, this comes at a price. Populism’s black and white views and uncompromising stand leads to a polarised society – for which, of course, both sides share responsibility – and its majoritarian extremism denies legitimacy to opponents’ views and weakens the rights of minorities". But this even-handedness should not be taken to imply a questioning of ideological priors. Mudde also says of populism: "It supports popular sovereignty and majority rule, but rejects pluralism and minority rights". The opposition of populism to pluralism remains central to liberal thought. In other words, the emphasis is always on the disputable claim to represent the people, not the shortcomings of the elite.
A push-back against the liberal interpretation of populism, which shifts attention from the people to the elite, can already be discerned, triggered by a desire for post-Brexit reconciliation in the UK and a realisation that the likely defeat of Trump will leave a fragmented polity in the US. This extends from pessimistic British conservatives like John Gray - "populism is a term of abuse applied by establishment thinkers to people whose lives they have not troubled to understand" - to class-conscious American critics like Sarah Smarsh - "That the term 'populism' has become a pejorative among prominent liberal commentators should give us great pause. A journalism that embodies the plutocracy it's supposed to critique has failed its watchdog duty and lost the respect of people who call bullshit when they see it" (the echo of the 1890s and 1900s is there in the dynamic of journalism - the original "muckrakers" - and plutocracy).
Populism is simply a democratic response to economic and social stress that questions the bona fides of the political establishment. That vulgar impertinence is its original sin. The dismissal of populism as lacking virtue (that horrible man) and competence (anti-expert, post-fact), may sometimes be legitimate, but it is also a continuation of Plato's argument against democracy. The last word goes to Marco D'Eramo, writing ahead of the present curve in 2013: "No one defines themselves as populist; it is an epithet pinned on you by your political enemies. In its most brutal form, ‘populist’ is simply an insult; in a more cultivated form, a term of disparagement. But if no one defines themselves as populist, then the term populism defines those who use it rather than those who are branded with it. ... Just as the adulterous spouse is always the one most suspicious of their own partner, so those who eviscerate democracy are the most inclined to see threats to it everywhere".