Veteran conservative activist Craig Shirley has called it "the height of intellectual dishonesty" to advocate repealing Roe while calling for the federalization of marriage. "[B]ehavioral issues belong at the state level," he observes.
Indeed, the conservative position on gay marriage—to say nothing of the consistent position—should be a federalist one. This is also the strategically sound liberal position, as TNR's James Kirchick argues:
[Federalism] appeals to conservatives who oppose gay marriage (like former Georgia Congressman Bob Barr [my link]) but agree that it is a subject best left for states. It also acknowledges that the president's power to enact legislation on gay marriage is extremely limited. The most a Democratic president could do is repeal the Defense of Marriage Act. . . . which would be a considerable accomplishment and open the door to granting federal benefits to gay couples in states where such unions are recognized. But marriage laws themselves [would] still [be] within the purview of the states.
Related: "Why Can't Democrats Explain Their Opposition to Gay Marriage?"
Update (8/22/07): The gay rights movement is often compared to the civil rights movement. But one parallel often overlooked is the importance of incrementalism.
For example, in 1957, civil rights leaders derided the Civil Rights Act as a sellout and a crippling compromise. But as (historian?) Robert Mann observed in an op-ed yesterday, "[B]y giving lawmakers confidence that voting for once-radical ideas wouldn't make the sky fall," the bill "paved the way for subsequent, stronger rights legislation."
Indeed, the monumental Civil Rights Act of 1964, like the Voting Rights Act of 1965, would never have passed in 1957.
The corollary: Same-sex equality won't happen tomorrow. It will proceed, to borrow a phrase from political scientist Phil Klinkner, as an unsteady march.