Across thousands of miles, Indian tribes, environmental activists, tourism promoters, and keelboat re-enactors saw the Lewis and Clark Bicentennial as a rare opportunity. The 200th anniversary of the expedition that helped open the West arrived at a time of seismic change in the region- a time when its economy, politics, and even population were shifting sharply. For three years, journalist and historian David Sarasohn followed the planning of the Bicentennial, recording how the past was being invoked to commemorate the Lewis and Clark Expedition and talking to those whose ideas were...