Obama’s transformation from opponent to champion of welfare reform is the latest in a series of moves to the center. Since capturing the Democratic nomination, Obama has altered his stances on Social Security taxes, meeting with rogue leaders without preconditions, and the constitutionality of Washington, D.C.’s, sweeping gun ban.

The shift in Obama’s rhetoric on welfare reform has proceeded in stages. When Clinton was poised to sign welfare reform while running for re-election in 1996, Obama called it “disturbing.” A decade later, as an underdog running for president against Clinton’s wife, he spent 2007 avoiding the subject. By the time Obama emerged as the Democratic frontrunner in the spring of 2008, he began leaving the impression that he was for it all along.

When implementation of welfare reform came before the Illinois state senate in 1997, Obama cited a lack of job training, insufficient oversight, and provisions blocking legal immigrants from receiving benefits as his reasons for opposing a federal welfare overhaul imposing work requirements and time limits.

While campaigning for president in 2007, Obama refused on two occasions to say if he would have signed the same welfare-reform bill approved by the husband of his top rival.

By glossing over his early opposition to welfare reform, Obama is stepping closer to the political mainstream. But by undergoing this transformation only once it became politically convenient, Obama’s critics will charge that he puts calculation ahead of conviction.