One of my favorite Adam Smith passages is:

The man of system … seems to imagine that he can arrange the different members of a great society with as much ease as the hand arranges the different pieces upon a chess-board. He does not consider that the pieces upon the chess-board have no other principle of motion besides that which the hand impresses upon them; but that, in the great chess-board of human society, every single piece has a principle of motion of its own, altogether different from that which the legislature might chuse to impress upon it.

Today, the men and women of system in the nation’s capital have a high regard for their ability to arrange the chess pieces of American society. There are 318 million individuals, 28 million businesses, 50 state governments, 89,000 local governments, and countless churches, charities, and other organizations in this great nation. Congress passes laws to intervene in the affairs of all of these people and groups, trying to impress its design.

But federal policymakers usually ignore, or fail to understand, the principles of motion in society. They impose minimum wages and health laws, and businesses cut hiring. They subsidize water, which exacerbates droughts. They subsidize flood insurance, which increases the damage from floods. They impose the world’s highest corporate tax rate, and they are shocked when corporations shift their profits abroad.

Federal attempts to arrange state government policies bring surprises as well. Federal policymakers offer matching grants for Medicaid, and are surprised that it prompts rapid state spending growth and dubious schemes to boost payments. Federal policymakers provide state aid for schools, but states probably just substitute added federal funding for their own.

The latest lesson on society’s principles of motion regards food stamp aid. From the Washington Post:

Congress last month passed a revamp of agriculture and food policy that was supposed to save the U.S. government $8.6 billion in food-stamp costs over a decade. That may not happen, though, now that some states are finding a way to avoid the cuts.

New York, Connecticut and Pennsylvania are triggering extra nutrition spending by adding money to a home-heating subsidy tied to increased food-stamp aid. The move feeds needy families while thwarting spending-reduction goals … If more follow, the federal government would have to spend much of the $8.6 billion it planned to save, as states reduce spending on other programs to meet the new mandate.

“These federal cuts have made it harder for our state’s most vulnerable residents to put food on the table. The state has intervened on behalf of these low-income New Yorkers,” Gov. Andrew M. Cuomo (D) said in a statement Feb 25. “New York is stepping up to help families in need.”