From the pork barrel to Pigasus - a hog nominated for president by the Yippies in 1968 - swine have served as an enduring American political metaphor. That's fitting given the outsize power of big agriculture, which extends even to this age of urbanization and our most urban state.

Consider New Jersey's latest messy encounter with pork policy. Gov. Christie recently vetoed a bill banning the use of so-called gestation crates, which large hog farms use to cruelly confine pregnant sows so closely that they can't turn around. Given the bill's overwhelming bipartisan support among New Jerseyans and in the Legislature - which may have the votes to override the veto - Christie's decision, like many of his most questionable acts, has been widely attributed to his presidential ambitions. The nation's first presidential caucuses take place in the big pig state of Iowa.

Indeed, Iowa's governor quickly praised Christie's veto even as it was roundly condemned by Democratic lawmakers, animal-welfare activists, Jersey-bred satirist Jon Stewart, and, of all people, Cher. According to the Daily Beast, Democratic State Sen. Ray Lesniak was fit to be hog-tied, going so far as to declare, apparently with a straight face, that the veto showed Christie is not "a good person," has no "moral compass," and puts his political ambition above "any sense of decency he may have left in his body."

But much as one might question Christie's pigheaded refusal of such a reasonable animal-welfare principle, one could wonder why this legislation ended up on his desk to begin with - and for the second time in as many years. New Jersey has only about 250 pig farmers and no widespread use of gestation crates. Attempting to regulate pork production from Trenton, in other words, is like trying to crack down on the mob from Des Moines. And while pork producers insist they can treat pigs any way they want, McDonald's and many other major buyers have already forsworn pork produced using gestation crates, suggesting the practice is on its way out.

New Jersey's Democratic Legislature is more likely motivated by an impulse to embarrass the Republican governor, who has of course cooperated by embarrassing himself. Beyond opportunistic politics as usual, we can thank Iowa's insane influence in a nomination process that empowers pork over people.