Submarines

They have been called the ultimate warship. The epitome of stealth. Today's submarines have come a long way from the submersible oak barrel that kicked off submarine warfare in 1776. Nuclear subs can remain underwater indefinitely and destroy targets thousands of miles away. Their strategic value is immense: ballistic-missile submarines account for half of U.S. nuclear defense capabilities. No modern military power could claim superpower status without these ships, nor prevail against challenges to its might.