Pros
The navy provides nearly limitless opportunity for professional and personal growth. The limiting factor is the motivation of the individual. Proven performance is rewarded with increased responsibility in high stress environments at a very young age. This level of trust is rarely found in other careers. The chance to represent the United States in situations that threaten our national security and way of life and a profound sense of pride in your work are additional benefits. World travel courtesy of the government, experiencing foreign cultures early and often, and making lifelong friends whom you can trust with your life should the need arise are all great reasons to work for the US Navy.
Cons
The major downside would be time away from home, crushing work hours (18-20 hour days back to back to back are not uncommon in an operational environment), and the politicking that sometimes goes on.