Editor's note: Eric Liu is the founder of Citizen University and the author of several books, including "A Chinaman's Chance" and "The Gardens of Democracy." He was a White House speechwriter and policy adviser for President Bill Clinton. Follow him on Twitter: @ericpliu. The opinions expressed in this commentary are solely those of the author.

(CNN) -- Want welfare? Pee here.

That's the message that a growing number of governors and legislators, mainly Republicans, are sending to their citizens. In statehouse after statehouse, new laws are being proposed and enacted that require recipients of food stamps, welfare, unemployment and other forms of public assistance to be able to pass a drug test first.

The idea, say these policymakers, is to ensure that precious tax dollars won't flow to undeserving free-riders with moral failings. Drug tests, they say, will motivate welfare recipients to clean up their acts and make themselves more employable all around.

There are so many things wrong with this. For one thing, it's the height of hypocrisy for limited-government conservatives like Wisconsin Gov. Scott Walker, who claim they want government out of people's lives, to champion such intrusive, shaming forms of paternalism. Moreover, these programs typically yield rather few cases of actual "welfare junkies."

More outrageous, though, is the selective morality at work. When politicians say they want to make public assistance conditional on clean drug tests, they don't mean all public assistance to all people. They mean assistance to the poorest among us. And with dog-whistle signals about "inner-city" welfare use, they often mean the brownest and blackest of the poorest among us.

That's why I find this drug-testing agenda repugnant. Yet it does prompt a thought experiment. Imagine, for a moment, if we took these moralistic politicians at their word.

Imagine if we instituted a policy nationwide that required anyone receiving taxpayer assistance to have to prove to the government that he or she is not using drugs. Then imagine if we meant every form of taxpayer assistance.

Are you the chief executive of Citigroup or another Wall Street firm that received many billions of dollars in TARP bailout money? Fill this cup, please. And if you subscribe to the belief that corporations are people because a corporation is an association of persons, then every person who works at Citigroup had better get in line, too.

After all, we want to make sure that precious tax dollars don't flow to undeserving free-riders with moral failings. But don't worry, testing financiers should motivate them to clean up their acts.

But it's not just Wall Street. Do you own a farm that receives federal payments to support the price of your crops? Did your business ever get a tax break to keep it from relocating? Does your factory pay unusually low electricity rates because of a nearby public power project? You must be a drain on the public coffers. Urination-on-demand is now your civic obligation.

And of course, it's not just about the 1% or businesses. Our federal latticework of direct subsidies and "tax expenditures" touches most of middle-class America.

So, imagine being told you must prove you aren't a drug user before you could claim a home mortgage interest deduction. Before your employer-provided health insurance could be considered excludable from taxes. Before you could receive a subsidized interest rate for your college loan.

Welfare -- in the form of subsidies, tax breaks and direct payments -- is everywhere. Sometimes submerged, sometimes visible. The point isn't that welfare is presumptively bad (or, for that matter, good). The point is that because it is everywhere, welfare in all its various forms should be treated alike.

So, if we want as a nation to attach a moral fitness test to the receipt of other people's money, let's do it across the board. Indeed, let's start with the premise that moral fitness requirements should be progressive — that the more welfare you receive, the more stringent and unforgiving the form of testing you should face.

Why don't these preening "welfare reformers" ever propose that? Ah yes, because that would require actual political courage.

Picking on poor citizens who get a few dollars of cash a day to feed themselves or pay the rent -- that's politically cost-free. Poor citizens don't usually vote. Poor citizens aren't usually visible enough to make others share in their suffering.

Poor citizens are, in short, the perfect punching bags for elected officials who want to look like they're tough.

But here's the thing that is unavoidable. Poor citizens are still citizens. To say the words "equal citizenship" with a straight face, we had all better ask ourselves where each of us would be without public assistance. And then perhaps be ready to join our poorest fellow citizens for a drug test.

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