10 



OCEAN SCIENCES AND NATIONAL SECURITY 



Even so, to a great extent, the British Navy served as a guardian 

 of the sea barrier and, for reasons of British foreign pohcy, made 

 practicable U.S. enforcement of the Monroe Doctrine. 



With mdependence, the new American Nation entered upon a 

 course of nationahsm which inchided a concentration of intellectual 

 and physical efforts toward the interior. By the 1830's and 1840's 

 "Manifest Destiny" was a widely accepted doctrine. That is to say, 

 the Americans were destmed to occupy, civilize, and populate the 

 continental land mass between the Atlantic and the Pacific. Some 

 Mexican territory fell before this urge to possess a continent; the 

 British compromised on their claims to what is now our Pacific North- 

 west. Oratorical enthusiasm sometimes extended the scope of 

 Manifest Destiny to all of the Western Hemisphere and all of the 

 Pacific basin. These larger imperial visions failed of fruition but did 

 lead to significant ventures beyond the territorial frontier. The 

 principal importance of Manifest Destiny was that the efforts and 

 focus of attention of the American people turned from the sea to the 

 interior. The relationship of the United States with the sea became 

 temporarily dormant. 



This implication of national policy was reflected in a changing 

 stature of the American maritime fleet. Its day of glory before the 

 Civil War was based on wooden ships and sail. While the traffic on 

 inland waterways converted quickly to iron and to steam, the overseas 

 fleet, failing to find either commercial or Government stimulation, 

 withered. Then, during the Civil War, the earlier trade patterns 

 were completely disrupted and many merchant vessels were destroyed. 

 Although well intentioned, the Federal Government adopted a series 

 of measures wliich did not revive the merchant fleet in the face of 

 vigorous competition, but in contrast, gave cash and land grants after 

 the Civil War to encourage the development of railroads. American 

 attention, once again, was focused on the heartland. 



At the end of the 19th century, the U.S. merchant fleet reached a 

 new ebb, a pattern clearly evidenced by the following table of the 

 capability of the merchant fleet.^ 



Year: 



1789. 

 1800_ 

 1810_ 

 1 S20_ 

 18:^0. 

 18-t0_ 

 1850, 

 1860_ 

 1870. 



Tonnage 

 123, 898 

 (J67, 107 

 081,010 

 588. G57 

 587, 568 

 762, 888 

 439, 604 

 379, 306 

 448, 846 



Year — Continued Tonnage 



1880 1,314,402 



1800 028,062 



1900 816, 705 



1010 782,517 



1020 9, 024, 694 



1030 6, 205, 935 



1940 8,637,617 



1950 8.358,000 



1958 6,208,000 



The disastrous effect of the Civil War and the decades of neglect 

 afterwards are readily apparent. World Wars I and II obviously 

 stimulated the expansion of the American merchant marme. Yet in 

 1958, only 13.6 percent of the total import and export cargo tonnage 

 of the Nation was carried in vessels flyhig the American flag. 



Just after the Civil War, Rear Adm. Alfred Thayer Mahan wrote 

 an important treatise remindmg the American people of the critical 

 role of seapower in history and its particular significance for the 

 United States. Mahan started from the fact obvious to any viewer 



» "Historical Statistics of the U.S., 1780-1945," and "Statistical Abstract of the U.S. 1959." 



