Invent a holiday! Explain how and why everyone should celebrate.

I have seen a movie long ago called the purge and it was about once a year for 12 hours you are allowed to do whatever you wanted without breaking in laws. I want a day full of peace meaning that everyone at war should be at peace at least those 24 hours a year. I know it will be hard but I am tired of all the war all the time and once read that the world has only been at peace for 2 hours since we started writing things down which is sad when we are one people. Guess I will add that you should give a present to your worst enemy, but otherwise I just want the peace.