SOME of the most valuable work in the field of American history these days is being done by the men and women who restore and preserve historical sites. Though such work is often disdained as antiquarian or subscholarly by academic historians, it in fact serves an immensely important public purpose. It helps us to remember our origins and, thereby, to remember who we are. Whenever one visits a reconstructed colonial American setting—and here I am thinking not only of a relatively elegant town like Williamsburg but also of somewhat more spare or rugged places such as Jamestown or Old Sturbridge Village or Plimouth Plantation or St. Mary’s City—one is forcibly reminded of the tentativeness, the contingency, the fragility, the sheer chanciness of the entire American undertaking.