Some of his comments are indefensible, and even some of Santorum’s defensible assertions would have been better left to someone else — someone not seeking the presidency — to say. Santorum’s remarks about Senator McCain were unwise and uncharitable. Nor do we need political leaders to share their theological judgments about the various denominations that call themselves Christian. There is no good reason for a prospective president to pledge to lecture Americans about contraception.

Social conservatives have an understandable and mostly laudable impulse to defend Santorum. He is one of us, he has fought for our causes, and he has the political scars to prove it. Santorum is not one of those Republicans about whom Richard Brookhiser once remarked, “In their hearts they know they’re wrong.” He seems serenely confident that with enough time he can change anyone’s mind on the issues. But he has not always shown that he knows how to pick his battles wisely, or that he understands that voters want a president with a suitably modest conception of a president’s proper role in national life. At an intellectual level Santorum must understand these points: He has not repeated his comment about using the presidency to turn the culture away from contraception. The challenge before him is to marry his self-confidence to a more consistent exercise of discrimination and tact.

If he does not heed this lesson, he risks doing damage to the causes he rightly holds dear.