Book excerpt: Arriving as the country commemorates the expedition's bicentennial, Across the Continent is an examination of the explorers' world and the complicated ways in which it relates to our own. The essays collected here look at the global geopolitics that provided the context for the expedition. Finally, the discussion considers the various legacies of the expedition, in particular its impact on Native Americans, and the current struggle over who will control the narrative of the expansion of the American Empire. --from publisher description.