America's post--Cold War strategic dominance and its pre-recessionaffluence inspired pundits to make celebratory comparisons to ancient Rome at itsmost powerful. Now, with America no longer perceived as invulnerable, engaged inprotracted fighting in Iraq and Afghanistan, and suffering the worst economicdownturn since the Great Depression, comparisons are to the bloated, decadent, ineffectual later Empire. In Why America Is Not a New Rome, Vaclav Smil looks atthese comparisons in detail, going deeper than the facile analogy-making of talkshows and glossy magazine articles. He finds profound differences. On the surface, the vision of America as the new Rome has resonance. There are obvious, intriguingparallels and amusing--even disconcerting--similarities. The America-Rome analogydeserves a closer look, and this is what Smil, a scientist and a lifelong student ofRoman history, offers. He does this by focusing on several fundamental concerns: thevery meaning of empire; the actual extent and nature of Roman and American power;the role of knowledge and innovation in the two states and the importance ofmachines and energy sources; and demographic and economic basics--populationdynamics, illness, death, wealth, and misery. America is not a latter-day Rome, Smilfinds, and we need to understand this in order to look ahead without the burden ofcounterproductive analogies. Superficial similarities do not imply long-termpolitical, demographic, or economic outcomes identical to Rome's.