There are over 190 nations in the world. Most are members of the United Nations. (There's some disagreement on the exact number, depending on the various list criteria and political agendas.) In each of those countries there is some form of "Independence Day" or patriotic founding celebration.
Patriotic holidays are important to solidify a society's cultural identity and growth.
But - and here enters the brainstorming - what about when we spread out to the stars and growing pains start?
First things first, how will the expansion start? (It lends to the brainstorm further down, promise.) I see a few ways it could go.
- The United Nations (or other unity organization yet to be created) purpose expands and solidifies all the countries and forges into the stars as one human nation. This is very Star Trek-ish.
- Private entrepreneurs and corporations will forge into the stars with the fiscal support of the strongest nations. These nations will then lay claim to the space they conquer. Much more Firefly-ish
- Private entrepreneurs and corporations will forge into the stars with fiscal support of private and group investors and the government concept will become corporatism.
What will that look like? Most of the current patriotic celebrations involve a certain date, fireworks, gatherings, food, music and honorary speakers.
Hmm... most of those won't work in space. Okay, gatherings, food and music seem pretty workable. But how about the date? That'll be a problem in a civilization spread across the solar system. Fireworks. Okay, granted, that could work on open planetary settlements, but what about domed facilities, space colonies and life vessels? And honorary speakers. This hits the same issues as a date. The distance will make any live speaker broadcast difficult.