John Vecchione writes at FrumForum that, no, David Frum had it right the first time - back when he believed in "conjugal marriage":

David  Frum has now thrown in the towel on same sex “marriage”. In point of fact his original view was correct. This conjugal view of marriage is the conservative position and easily defended by those with the wit and heart to do so.

... In New York the damage to the Republican Party will be lasting and swift.  If a Republican controlled Senate does not stop same sex marriage, and indeed calls it an emergency measure and passes it with the skullduggery we have come to expect from all gay rights victory of this decade-there is no reason for social conservatives to support the party.  The news outlets have been crowing about the moneyed Republican gay rights elites fixing this deal.

The non-moneyed, non-elites have votes.  They know who caved and they will react by ousting them or staying home.  Either will destroy what is left of the Republican Party in New York.  New York now stands as a test case for the idea that a socially liberal Republican Party will be a stronger Republican Party.  The New York Republican Party could hardly be weaker — but weaker it will be.  They will lose the Senate in the next election.  The only redoubt of the Party in the State has been punted to support a policy that is a priority only for those who hate Republicans and conservatives with the fiercest intensity.  The dim merits of same sex marriage aside this was politically idiotic.

... Mr. Frum’s change of heart on this issue seems to be because same sex marriage in a few states has not lead to family Armageddon.  Why is that the standard?  Are conservatives only allowed to oppose something if it creates an absolute catastrophe, or are they allowed to oppose policies that marginally injure important institutions?

... his is the view that marriage has already been destroyed by the consequences of the 60’s so who cares?  I adhere to the view that liberalism can always make a bad situation worse, particularly if its view is codified.

The rest is well worth reading too!