The typical one-term president generally falls into the “average” category, occasionally showing up as “above average.” This generally means no unavoidable crises, no scandals of consequence and no serious new directions for America. A 2000 Wall Street Journal poll of historians ranked John Adams as above average and then populated the average category mostly with one-termers: William Howard Taft, John Quincy Adams, George H. W. Bush, Rutherford B. Hayes, Martin Van Buren and Chester A. Arthur.

Also on the “average” list were the two-termers Calvin Coolidge, whose economic policies are viewed by many historians as having contributed to the Depression, and Bill Clinton, whose historical reputation couldn’t be judged fairly before his presidency was over. (Similarly, it’s too soon for historians to assess George W. Bush, however tempting that may be.) Most of these “average” presidents were decent men and serious politicians, but they left little mark of historical dimension upon the nation.

All this suggests a false dichotomy underlying Mr. Obama’s expressed resolve to render his presidential decisions without regard to his re-election chances — as if the choice were between political popularity and governmental success. A better approach for any chief executive is to assume that, in presidential politics, as in retailing, the customer is always right, and that the electorate’s verdict will be consonant with history’s consensus. Thus, the aim of every historically minded president, Mr. Obama included, should be to pursue a second term by bundling up voter sentiment into a collection of policies and programs that succeed in the crucial areas most on the minds of the American people.