For the most part, modern elections are narrow arguments about politics and policies - about whether a nation will swing two or three degrees left or right from the prevailing consensus. The effects are felt at the margin: the rich get a bit richer or, perhaps, the poor feel a little less oppressed. Then, once in a while, voters have a chance to look in the mirror and make a profound choice about a nation's character and values. Such is the contest between George W. Bush and John Kerry. One way or another next Tuesday's poll will answer the most compelling question of our times: what sort of country does America want to be?

I have heard many people say otherwise. Self-styled political realists have converged on the notion that there is nothing much to choose between the Republican president and his Democratic challenger. America will wake up on Wednesday to much the same problems. Al-Qaeda will not be any kinder to Mr Kerry than to Mr Bush. Stripped of campaign rhetoric, the competing candidates have similar answers. The differences are of tone and style more than substance. In any event, whoever wins will be hemmed in by awkward realities.