“The beginning of wisdom is the fear of the Lord. The next and most urgent counsel is to take stock of reality.”

— William F. Buckley,

Sept. 11, 1964

On that evening 48 years ago — it was still summer, early in the presidential campaign — Buckley, whose National Review magazine had given vital assistance to Barry Goldwater’s improbable capture of the Republican nomination, addressed the national convention of the conservative Young Americans for Freedom. Buckley told his fervent acolytes that “when we permit ourselves to peek up over the euphoria” of Goldwater’s nomination, we see that it occurred “before we had time properly to prepare the ground.”

He then sobered his boisterous audience: “I speak of course about the impending defeat of Barry Goldwater.” He urged “the necessity of guarding against the utter disarray that sometimes follows a stunning defeat.” Goldwater’s doomed campaign should, Buckley said, be supported because it plants “seeds of hope, which will flower on a great November day in the future.” They did, 16 Novembers later.

Buckley understood the possibility of constructive defeat. He also understood the need to economize conservatism’s energies.

Today, conservatives dismayed about the Republican presidential spectacle may write a codicil to what is called the Buckley Rule. He said that in any election, conservatives should vote for the most electable conservative. The codicil might be: Unless the nomination or election of a particular conservative would mean a net long-term subtraction from conservatism’s strength.

If nominated, Mitt Romney and Rick Santorum might not cause such subtraction. Both are conservatives, although of strikingly different stripes. Neither, however, seems likely to be elected. Neither has demonstrated, or seems likely to develop, an aptitude for energizing a national coalition that translates into 270 electoral votes.

If either is nominated, conservatives should vote for him. But suppose the accumulation of evidence eventually suggests that the nomination of either would subtract from the long-term project of making conservatism intellectually coherent and politically palatable. If so, there would come a point when, taking stock of reality, conservatives turn their energies to a goal much more attainable than, and not much less important than, electing Romney or Santorum president. It is the goal of retaining control of the House and winning control of the Senate.

Several possible Supreme Court nominations and the staffing of the regulatory state are among the important reasons conservatives should try to elect whomever the GOP nominates. But conservatives this year should have as their primary goal making sure Republicans wield all the gavels in Congress in 2013.

If Republicans do, their committee majorities will serve as fine-mesh filters, removing President Obama’s initiatives from the stream of legislation. Then Republicans can concentrate on what should be the essential conservative project of restoring something like constitutional equipoise between the legislative and executive branches.

Such a restoration would mean that a reelected Obama, a lame duck at noon Jan. 20, would have a substantially reduced capacity to do harm. Granted, he could veto any major conservative legislation. But such legislation will not even get to his desk because Republicans will not have 60 senators. In an undoubtedly bipartisan achievement, both parties have participated in institutionalizing an extra-constitutional Senate supermajority requirement for all but innocuous or uncontroversial legislation. This may be a dubious achievement, but it certainly enlarges the power of a congressional party to play defense against a president.

Three years ago, conservatives were particularly focused on stopping two of Obama’s principal goals — a cap-and-trade climate policy and “card check” to abolish secret ballots in unionization elections. He still speaks incessantly but no longer speaks about either. And were it not for grossly corrupt conduct by Justice Department prosecutors in the trial of Sen. Ted Stevens (R-Alaska), which cost him reelection, Obamacare would not have passed.

Beginning next January, 51 or more Republican senators, served by the canny Mitch McConnell’s legislative talents, could put sand in the gears of an overbearing and overreaching executive branch. This could restore something resembling the rule of law, as distinct from government by fiats issuing from unaccountable administrative agencies exercising excessive discretion.

From Louisiana Gov. Bobby Jindal to Wisconsin’s Rep. Paul Ryan, Republicans have a rising generation of potential 2016 candidates. This does not mean conservatives should be indifferent to the fate of this year’s nominee, and it is perhaps premature to despair of Romney’s and Santorum’s political aptitudes. Still, the presidency is not everything, and there will be another election in the next year divisible by four.

georgewill@washpost.com