Senator Santorum’s decision to bow out of the Republican primary campaign is a disappointing moment in a quest that we’d have preferred to see taken all the way to the convention. But the New York Times is reporting this morning that “his strong performance in a brutal nominating contest established him as a force that the party will probably have to reckon with this presidential election year and beyond.” We agree with that assessment, save for the adverb “probably.” Mr. Santorum’s great achievement in this campaign was to mark the size and staying power of the constituency for whom the so-called social issues rank with our economic and foreign policy problems. That this constituency will have to be reckoned with strikes us as a certainty.

So this is both an opportunity and a challenge for Governor Romney. He has proved to be a cheerful and durable candidate, but he is not yet fully tested on one of the characteristics that these columns look for in a leader. This is the ability to maintain over a long period of time a politically incorrect position. In respect of a preparedness to stand for a pro-life position, to levy a robust defense of the rights of even our most religious countrymen, to seek the enforcement of American law requiring the movement of the United States embassy in Israel to Jerusalem — on these and related issues, Senator Santorum has been articulate, constitutional, and unapologetic. He just didn’t leave the kind of doubts that are left by all too many others.

Governor Romney, deep in his heart, agrees with Senator Santorum on most of the social issues. That is, at least, our guess. But the governor has exhibited a more ambiguous public stance. No doubt there is an element of calculation in this. It may be that President Reagan, in erecting his big conservative tent, made a similar calculation, making his principles clear but also showing a certain cheerful openness. For our part, we are not immune to the siren of liberality. Our country, though, has been hearkening to this siren for so long that we are in danger of abridging the rights of our most religious citizens. This is widely sensed, and accounts for the breadth and intensity of the following that Senator Santorum was able to lead  into this contest.

So the logic is for Messrs. Romney and Santorum to find a modus vivendi for carrying the senator’s issues into the platform building process and into the campaign. We don’t mean to suggest that Mr. Santorum is the right vice presidential candidate for Mr. Romney. There will be a rich field from which to choose. Nor will Mr. Santorum’s followers be the only one’s that a successful nominee will have to bring into the fall campaign. We think here of the army of idealists behind Congressman Ron Paul, whose campaign for liberty, constitutional fundamentalism, and sound money has been the most intellectually exciting feature of this campaign. We’ll write more about that when Dr. Paul does what Mr. Santorum did yesterday. Suffice it to say that Mr. Santorum, in bringing the social issues to the fore, has given Mr. Romney a gift, and his challenge will be to make the most of it.