Many conservatives and tea party types talk a good game about shrinking government and cutting spending, but also react virulently when an entitlement they cherish, like Social Security and Medicare, is threatened. Progressives love to mock the tea partiers who demand, "Get your government hands off of my Medicare!" It gets laughs. And sure, fair enough.

But this conservative attitude isn't just rank hypocrisy. It also gets at some key aspects of the way our political life is set up.

So for starters: What's the conservative worldview? The writer Reihan Salam hit the nail on the head when he described the view of conservative activists as "reap what you sow economics." It's not just an issue of distribution or GDP, it's also one of fairness: If you work hard and succeed, you should enjoy the results of that work — if you don't, the system needs to push you to shape up.

This worldview is why President Obama's "you didn't build that" comments caused such a furor on the right — by seeming to deny what conservatives view as a key foundation of a prosperous and just society.

Everyone subscribes to some version of "reap what you sow economics." That's what capitalism is based on, and by now pretty much everyone understands that at least some capitalism is required for people not to starve to death. Almost no conservative disagrees with the idea of using tax money to build roads, and almost no progressive wants to nationalize Google and send Larry Page to a reeducation farm.

And this "reap what you sow" philosophy is actually compatible with a welfare state. To use celebrated slogans, "helping those who can't help themselves" and giving "a hand up, not a hand out" involves government safety net programs — if you can't sow, you can't reap. Conservatives are fine with such programs, so long as they are tailored to edge cases and designed to help beneficiaries become self-reliant.

But doesn't that mean conservatives should reject universal middle-class entitlements like Social Security and Medicare?

The answer is yes, mostly. But a simple yes misses one of the central facts of the American political economy, one that exposes progressive, and not conservative, hypocrisy: Middle-class entitlements are not individual savings schemes, even though they are often portrayed that way. This leads to some key confusion about these programs. This confusion is by design. From the New Deal to the Great Society era, the progressive architects of the American welfare state knew that the best way to ensure the political viability of these programs was to portray them as savings schemes.

The most common piece of rhetoric used to defend these programs is that once you had "paid into" them throughout your working life, you are entitled to the benefits you paid for. You are entitled to reap what you have sown.

But this is not how Social Security actually works. What you sow goes into a giant black hole. What you reap comes out of that same black hole, but it doesn't have all that much to do with what goes in, at least not directly. Instead of reaping your own crops, you reap your children's crops, but that is artfully concealed.

If the true nature of these programs was widely understood, I really believe that conservatives would rebel against them en masse, as would a sizeable number of the rest of the American public. Fortunately for the progressive project, the deception still holds.

So there you go. This conservative "get your government hands off my Medicare" attitude is deeply misguided, yes. But in a way, that points to progressive hypocrisy, too. Because the whole liberal entitlement system is built on misunderstanding.

Still, I guess progressives ought to be entitled to laugh — after all, they pulled off the most successful con job in American politics.