The meaning behind SF's famed Fleet Week

What people see at Fleet Week is just the tiniest tip of a gargantuan organization we call the United States Navy, the 247-year-old military branch that's on display this week. Fleet week celebrates the purpose, the power and the people of America's Navy.    But, by sheer volume, the U.S. Navy, with 480 warships and submarines ranks fourth, behind China with 777 , Russia with 603, and North Korea with 492. But where it really counts, the U.S. Navy has the most heavily armed, most technologically superior, best crewed ships on the planet. The tonnage of its active battle fleet alone is more that next 13 navies combined.