| The United States became the 
    world's first modern democracy after its break with Great Britain (1776) and 
    the adoption of a constitution (1789). During the 19th century, many new 
    states were added to the original 13 as the nation expanded across the North 
    American continent and acquired a number of overseas possessions. The two 
    most traumatic experiences in the nation's history were the Civil War 
    (1861-65) and the Great Depression of the 1930s. Buoyed by victories in 
    World Wars I and II and the end of the Cold War in 1991, the US remains the 
    world's most powerful nation-state. The economy is marked by steady growth, 
    low unemployment and inflation, and rapid advances in technology. 
 
      
        | Location: | North America, bordering 
        both the North Atlantic Ocean and the North Pacific Ocean, between 
        Canada and Mexico 38 00 N, 97 00 W
 |  
        | Population: | 278,058,881 (July 2001 
        est.) |  
        | Area: | total:  9,629,091 sq 
        km land:  9,158,960 sq km
 water:  470,131 sq km
 note:  includes only the 50 states and District of Columbia
 about one-half the size of Russia; about three-tenths the size of 
        Africa; about one-half the size of South America (or slightly larger 
        than Brazil); slightly larger than China; about two and one-half times 
        the size of Western Europe
 |  
        | Climate: | mostly temperate, but 
        tropical in Hawaii and Florida, arctic in Alaska, semiarid in the great 
        plains west of the Mississippi River, and arid in the Great Basin of the 
        southwest; low winter temperatures in the northwest are ameliorated 
        occasionally in January and February by warm Chinook Winds from the 
        eastern slopes of the Rocky Mountains |  
        | Terrain: | vast central plain, 
        mountains in west, hills and low mountains in east; rugged mountains and 
        broad river valleys in Alaska; rugged, volcanic topography in Hawaii |  
        | Elevation: | lowest point:  Death 
        Valley -86 m highest point:  Mount McKinley 6,194 m
 |  
        | Natural 
        resources: | coal, copper, lead, 
        molybdenum, phosphates, uranium, bauxite, gold, iron, mercury, nickel, 
        potash, silver, tungsten, zinc, petroleum, natural gas, timber |  
     
 
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