Robert Stacy McCain calls the anti-marriage stance a "hill [for Republicans] to die on." His reasoning:
Nothing succeeds like success and nothing fails like failure. Ergo, to defeat the radicals in their latest crusade (whatever the crusade may be) is to demoralize and weaken their side, and to embolden and encourage our side. Even to fight and lose is better than conceding without a fight because, after all, give 'em an inch and they'll take a mile.
But let us contemplate his metaphor: "a hill to die on."