You can get a bead on the difference between conservatives and liberals in this respect by comparing the rhetoric coming from Paul Ryan and President Obama about what counts as responsible budgeting. Ryan will bend your ear off about the monumental choice we're confronting between the conservative and liberal vision of society. Obama says his budgetary priorities aren't liberal or conservative; they're a matter of elementary mathematics. You can also see the same dynamic operating in a recent exchange between Russ Roberts and Paul Krugman over the validity of Keynesian economics.
According to Roberts, it’s a sign either of the conceptual crudity of modern macro-economics or the inherent complexity of its subject-matter that neither Keynesianism nor competing theories are readily testable. So we shouldn’t expect our profound differences over fiscal policy to be settled within macro-economics on empirical grounds. Roberts thinks that honest and self-aware economists should therefore acknowledge that their macro-economic theories are importantly a function of their ideological commitments respecting the size and scope of government:
“Krugman is a Keynesian because he wants bigger government. I’m an anti-Keynesian because I want smaller government. Both of us can find evidence for our worldviews. Whose evidence is better? I’m not sure it’s a meaningful question. My empirical points about Keynesianism won’t convince Krugman. His point[s] don’t convince me. I am not saying that we will never get any kind of decisive evidence on the question. I’m saying it sure isn’t here now.”As far as Krugman’s concerned, however, all that’s just a confession of intellectual sloth on Roberts’s part: “Russ Roberts may choose his economic views because they support his political prejudices. I try not to.” The intellectual self-righteousness is vintage Krugman. Part of the background noise you’re hearing are murmurs of appreciation from liberals at hearing him speaking the simple truth about intellectual hackery among economic conservatives. The rest of the noise comes from conservatives' howls of derisive laughter at Krugman’s professions of ideological innocence.
I confess that, although I stand on Krugman’s side of this ideological barricade, I can’t help chuckling along with the conservatives at his pretense that the barricade exists only in the mind of intellectually flabby conservatives like Roberts. Consider Krugman’s “argument” to the effect that his Keynesianism can’t be an expression of an ideological predisposition for “big government” (i.e., for widening the allocative and distributive scope of government at the expense of markets) because liberals like him don’t have one:
“[W]hile conservatives see smaller government as an end in itself, liberals don’t see bigger government the same way. Think about it: while you often see conservatives crow about, say, reducing discretionary spending as a good thing just because the number is down, do you ever see liberals crowing about a rise in spending, never mind what on? Liberals want government to do certain things, like provide essential health care; the size of government per se isn’t the objective.”This, of course, is nonsense. Conservatives don't think "the smaller the government the better" any more than liberals think "the bigger the government the better.“ Both conservatives and liberals want government to perform certain allocative functions and leave others to the marketplace. And both want government to spend every penny it takes to discharge the allocative functions it properly undertakes and not a penny more. The pertinent difference between them is that liberals want government to perform all the allocative functions that conservatives want it to perform and many more. Krugman would have you believe that things just happened to work out this way after liberals made a series of case-by-case pragmatic judgments.
I’m not sure whether Krugman is just letting his polemical zeal get the better of him, or whether there’s a gaping hole in his ideological self-consciousness. Conservatives don’t need to be advised that they entertain a strong presumption in favor of allocating things through markets. It’s not an irrebutable presumption, mind you, because they recognize that government is properly in the business of producing certain public goods, like national defense, law-and-order and infrastructure, the production of which invites market failure.
But when it comes to deciding whether any particular good should be produced and distributed via markets or the political process, conservatives quite self-consciously place the burden of proof on those arguing for allocation through the political process. That’s because, as most conservatives see it, markets aren’t just one social allocation system among others to be judged according to our idea of who should end up with what. Their default assumption is that you need a very good reason for getting in the way of market transactions because markets arise spontaneously whenever free individuals interact with each other.
There’s not much point in calling yourself a liberal unless you embrace a conflicting presumption, viz., that markets are just one way of distributing goods and bads among the population that should answer to our standards of distributive justice. Liberals support mixed economies in which markets do most of the allocative work because they think they enable people near the bottom of the economic pyramid to be better off in absolute terms than they would be under a more socialized economic system. But they lay the burden of proof at the feet of free marketers to show that markets will yield better distributive results than you can get out of the political process.
Roberts’s anti-Keynesianism and Krugman’s Keynesianism uncannily track the foundational presumptions of their respective ideologies. Roberts doesn’t think Krugman has, or can, meet his burden of proving that the government spending more borrowed dollars will jump-start an economy mired in a liquidity trap. Krugman doesn’t think that Roberts has, or can, meet his burden of proving that markets will clear faster, and the economy will start growing again sooner and faster, if government gets out of their way. So what else is new.
Roberts, however, has it in him to step back from polemical fray far enough to acknowledge the real possibility that they could both be right. For reasons that elude me, Krugman seems to think that it speaks well of him that he doesn't.