Big mood. Photo: Pacific Press/LightRocket via Getty Images

The American public is in the mood for “big government.” According to the distinguished political scientist James Stimson’s “Public Policy Mood estimate” — a widely respected tool for measuring shifts in ideological opinion across time — the U.S. electorate is more sympathetic to left-wing economic policy today than at anytime in the past 68 years (which is as far back as Stimson’s data goes).

Tracking ideological change across decades is inherently difficult, since some policy questions fall out of surveys as time passes, while others enter them. And what qualifies as the “liberal” or “conservative” position on a given issue can also evolve over time. This is most conspicuously apparent on social and cultural policy, where Barack Obama’s 2008 position on gay marriage would put to the right of some congressional Republicans in 2019.

But Stimson’s index confines itself to the role of government in the economy, or as he puts it, “the New Deal and Great Society agendas.” And on this dimension of public opinion, the arc of history has most definitely not bent in a consistently liberal direction. In fact, before the American public’s mood hit a new peak for economic liberalism in 2018, the high point for such attitudes had been 1961.

To the extent that there is a consistent pattern in the evolution of Americans’ ideological attitudes in Stimson’s data, it is a thermostatic one: When a Republican is in office, or the bent of federal economic policy moves right, public opinion tends to move left, while Democratic presidents, or liberal policy initiatives, tend to provoke the opposite reaction.

That said, the public’s newfound enthusiasm for left-wing economic policy probably isn’t purely a product of fickle swing voters reflexively changing their stripes. While Donald Trump did make cutting social spending for the poor — and slashing taxes on the rich — his top legislative priorities upon taking office, appeals to “small government” conservatism have never featured all that prominently in his rhetoric. In fact, the president insisted that his tax cuts would not benefit the wealthy, and that his push for Obamacare repeal would result in universal coverage at affordable prices (as opposed to deficit reduction, or some other objective consistent with the actual substance of his party’s policy). And Trump isn’t the only member of his party who has ceased to forthrightly argue for conservative economic priorities. Many Republican candidates campaigned on their support for preserving subsidized health insurance for Americans with preexisting conditions last fall, even as they actively worked to undermine such protections in Congress and the courts.

This mendacious messaging was likely a response to public opinion; while voters’ views vary across time, giving rich people tax breaks and throwing sick people off their health insurance have never been popular ideas in American politics. But the fact that many leading Republicans have ceased to advocate for fiscal conservatism — while the party’s standard-bearer has, at least rhetorically, championed an active role for government in shaping economic outcomes — might have played a part in pushing Stimson’s mood index left. Many partisan voters do not have strong intrinsic preferences on many economic issues, which can often appear more technical than moral. Thus, they will often take their ideological cues from partisan elites. With a growing number of conservative commentators and Republican politicians making populist noises on economic policy (however disingenuous), it wouldn’t be surprising to see GOP voters’ views start trending more liberal. And considering that Democratic elites have also shifted left in their economic messaging over the past two years, it’s possible that elite signaling accounts for much of the trend Stimson documents.

Regardless, the liberal turn in the public’s mood last year may ultimately prove less consequential than the leftward drift in the economic thinking of America’s elite policy wonks over the past decade.

As we’ve seen, public opinion is fickle and exercises only limited influence on policy outcomes. But changes in the conventional wisdom among elite policymakers are often durable and have the power to redefine the terms of the “left versus right” debate. And economic events since the 2008 financial crisis have made it quite difficult for all but the most hackish apologists for upward redistribution to avoid revising their views in a leftward direction.

For example, in the immediate aftermath of the crash, many respectable thinkers on the center and right believed in the concept of “expansionary austerity” — the notion that slashing deficits could spur higher growth, even in a context of relatively low demand. European countries structured their response to the crisis around this theory; the United States, by contrast, pursued a conventionally liberal (in the New Deal sense) Keynesian response to the crisis, running up its short-term deficit for the sake of stimulating demand. Thus, the Western world effectively conducted a natural experiment testing the “expansionary austerity” hypothesis — an experiment that utterly discredited fiscal conservatives. Countries that prioritized deficit reduction saw employment and growth fall off a cliff, while the U.S. economy embarked on a historically long expansion (albeit one that could have been even more robust had the austerians not intimidated the Obama administration into proposing a smaller stimulus than its economics thought warranted).

And if this empirical embarrassment weren’t enough, one of the major papers undergirding the expansionary austerity theory proved to be incorrect on its own theoretical terms — the research’s key findings were premised on an Excel formula error.

These events damaged the credibility of deficit hawks. And the fact that the United States proceeded to carry on pushing up its debt to record levels — while retaining the ability to borrow money at rock-bottom interest rates, and experiencing an undesirably low rate of inflation — further eroded the standing of those who preached the supreme importance of fiscal rectitude, even in the face of high unemployment and low demand.

Another related pillar of pre-crisis conservative economic orthodoxy was that policy-makers must not allow the unemployment rate to fall too low — or workers’ bargaining power to rise to high — or else workers would be able to extract wages in excess of their own productivity, which would lead to price increases, which would produce further demands for excessive wages, thereby setting off an inflationary spiral that would discourage investment and shrink the economy’s productive capacity.

This fear of runaway inflation led conservative economist Marvin Goodfriend to warn that if the Federal Reserve allowed the unemployment rate to dip beneath 7 percent, it would likely “give rise to a rising inflation rate in the next few years, which would just be disastrous for the economy.”

Of course, the unemployment rate in the U.S. is now 3.6 percent, and both inflation and wage growth are lower than the Fed would like them to be. In this context, the case for suppressing full employment — or the bargaining power of workers by discouraging unionization — is exceptionally weak. Especially since America’s top corporations could afford to be paying their workers much more without raising prices or reducing investment. In fact, these firms are simply sitting on trillions of dollars in cash, unable or unwilling to find productive investments for their capital. The conservative economists’ solution to that problem, of course, was to incentivize investment by cutting corporate tax rates — but that resulted in one more natural experiment that contradicted conservative orthodoxy.

Don’t take my word for it — take Marco Rubio’s. In his office’s recent report on the decline of business investment in the United States, the Florida senator admits that, while the Trump tax cuts “were often expressly advocated for as a means of on-shoring corporate residence and increasing capital investment,” the legislation has shown little sign of reversing the historical decline in such investment.

Anyhow, this is far from a comprehensive catalogue of how post-financial-crisis trends have undermined conservative economic arguments. (The Week’s Ryan Cooper ably dissects a couple others here, while the economist J.W. Mason offers a guided tour of his profession’s decade of embarrassments here.) The point is that economists who favor increasing worker power, promoting full employment, stimulating demand, and having the public sector play a more active role in channeling investment now have a lot more empirical ammunition at their disposal than they did a decade ago — while those who champion fiscal austerity, a hawkish posture on inflation, and supply-side tax cuts as a panacea for increasing productive investment have far fewer arrows in their quiver.

And it shows. The Democratic Party’s leading economic thinkers have ceased worrying about deficits and grown far friendlier to organized labor and comfortable with sweeping state interventions in the economy to mitigate inequality and facilitate socially beneficial investment. And while the Republican Party’s finest hacks have carried on supplying the same rationalizations for plutocracy they always have, other GOP policy wonks (like those working in Rubio’s office) and center-right think tanks (like the Niskanen Center) have been gravitating away from supply-side dogma and toward the formerly “liberal” terrain of industrial policy.

When the next Democratic president takes office, there’s a decent chance that the public’s policy “mood” will shift back to the right. But barring some radical change in macroeconomic reality, the boundaries of America’s economic debate will still (almost certainly) still lie to the left of where they’ve been for most of the past four decades.