Interesting that the ocean is still the cheapest way to transport goods worldwide.
If you want a fun quick read, pick up George Friedman's The Next 100 years
Amazon.com: The Next 100 Years: A Forecast for the 21st Century (9780385517058): George Friedman: Books
He talks about how US domination of the oceans is an unwritten cornerstone of our policy to command the global economy.
-spence