More broadly, until Rep. Paul Ryan’s recent prominence, nobody in Congress has been as passionate and fearless an advocate for entitlement reform as Santorum. Medicaid block grants. Investment accounts for Social Security. Medicare payments controlled by the beneficiaries rather than third-party payers. Choice rather than government mandates. Indeed, Santorum was the first candidate this year to fully embrace Ryan’s proposed reforms — with this exception, as he reminded me in a phone interview on Thursday: “I’ve criticized Ryan on one thing: waiting ten years [for many of the reforms to kick in]. We can’t afford to wait. We’ve got to start now.”

It was his enthusiasm for entitlement reform (probably combined with pressures from being in the Senate leadership at the time, although he won’t say so) that, Santorum says, led him into the vote about which rightward critics most often carp: the creation in 2003 of the Medicare Part D prescription-drug program. As expensive as it was, Part D did embrace three conservative goals.