What would it be?
Rule 1: You can only warn them of one thing.
Rule 2: You can't choose what someone else posted.
Rule 3: You can travel as far back as your country's founding, but no further.
Rule 4: You're limited to just your country.
Rule 5: You're only allowed to warn them of what's to come within the next 10 years from what year you travel to.
Rule 6: If you travel to your country's founding, your warn limit is 100 years.
Rule 7: If you travel to a moment of a great historical achievement, your warn limit is 50 years.
I know a lot of people will go for this one so I'm getting it out of the way first.
I'd go back to 1999 and warn people of the September 11 terror attacks.
Choose something different and keep it interesting.
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I am sick, and in so being I am the healthy one.
If my darkness or eccentricity offends you, I don't really care.
I will not apologize for being me.
There is no such thing as perfect. We are beautiful as we are. With all our imperfections, we can do anything.