With Republican senators like Rob Portman (Ohio), Mark Kirk (Ill.) and Lisa Murkowski (Ala.) recently announcing they now support gay marriage, openly gay Republican representatives like Missouri’s former state Rep. Zachary Wyatt and Massachusetts’ former state Sen. Richard Tisei, and pressure from groups like GOProud and Young Conservatives for the Freedom to Marry, it’s clear that — like Pope Francis — today’s big tent is sitting on shifting ground.

As I’ve said before, the GOP doesn’t need to embrace same-sex marriage. There are conservatives in Congress — and Americans all over the country — for whom gay marriage is simply counter to their values. Those Americans shouldn’t be judged either. Similarly, despite Pope Francis’s words of acceptance, I don’t expect the Catholic Church to begin promoting gay marriage. It doesn’t need to. …

Popular opinion is never a reason for a group to abandon its principles. But when its principles are so obviously in conflict not only with the group’s survival, but with the group’s stated philosophy — in this case, one that abhors big government intrusion into private life and champions monogamy and stability within marriage — it’s time to consider softening, not abandoning, those principles.