Today I turned 18. In my mind this is the most important birthday I will have. It ranks one out of three: 13, 18, and 50.
In Jewish culture, when a boy turns 13, he becomes a man after under going a Bar Mitvah. In today's society, 13 still marks the age at which a child gains more trust and responsibility.
50 marks a half-century of life, and all the knowledge that comes with it.
18, however, marks something else entirely. It marks the point at which a person can finally give back to society. Instead of just taking up resources, one can finally work to create them. Instead of complaining about the world, a person can finally change it. Instead of merely enjoying freedom, one can finally defend it.