A compromise on federal civil unions?

From Sunday's New York Times, a joint op-ed by David Blankenhorn and Jonathan Rauch advocating federal recognition of state-conferred same-sex marriages and civil unions, with an asterisk:

It would work like this: Congress would bestow the status of federal civil unions on same-sex marriages and civil unions granted at the state level, thereby conferring upon them most or all of the federal benefits and rights of marriage. But there would be a condition: Washington would recognize only those unions licensed in states with robust religious-conscience exceptions, which provide that religious organizations need not recognize same-sex unions against their will. The federal government would also enact religious-conscience protections of its own. All of these changes would be enacted in the same bill. . . .

Linking federal civil unions to guarantees of religious freedom seems a natural way to give the two sides something they would greatly value while heading off a long-term, take-no-prisoners conflict. That should appeal to cooler heads on both sides, and it also ought to appeal to President Obama, who opposes same-sex marriage but has endorsed federal civil unions. A successful template already exists: laws that protect religious conscience in matters pertaining to abortion. These statutes allow Catholic hospitals to refuse to provide abortions, for example. If religious exemptions can be made to work for as vexed a moral issue as abortion, same-sex marriage should be manageable, once reasonable people of good will put their heads together.

Rauch and Blankenhorn are among the ablest defenders of their respective positions, pro and con gay marriage, in the country. Both have written excellent books on the subject. What they say will be noticed by all sides, especially because they say it together. There will be strong objections on both sides: from SSM opponents who oppose recognition in principle and not just for instrumental reasons, and from SSM supporters who will worry about the practical consequences and who will wonder why such marriages alone will be qualified by morals exemptions.

There is much to think about here. A conditional offer of federal recognition would be a powerful inducement to the states since they won't want their recognized gay relationships excluded from federal advantages. For SSM supporters, that's good if it speeds state-based recognition of gay families but not so good if it hollows out that recognition.

My initial and very tentative reaction, as a same-sex marriage supporter, is that the Blankenhorn-Rauch compromise probably gives little away since SSM was never really a threat to religious liberty anyway. As a practical matter, gay families gain a lot in very important federal benefits in exchange for what appears to be barring lawsuits that either weren't -- or shouldn't -- be available. The devil is in the details -- what exactly do "robust religious-conscience exceptions" cover? -- but the op-ed starts a conversation about federal legislation that might be politically achievable in the near future.