I'd disarm the Middle East.
End all wars, and the reasons for them, and spend defense money on more useful things such as food and water for the poor nations, medical research, homelessness, etc.
The lack of compassion and intolerance for people who are different.
I'd change who's running for president in the 2016 U.S. Election. Not to get political, but the though of any of the candidates in office scares me. Not saying who'd I would have running instead. But I would remove those running now.
Or perhaps I'd change the U.S. National debt. That's an $18 trillion dollar issue. . .
I had contemplated some epic, sweeping change like desalinizing the oceans, eliminating poverty, or ridding the world of Kardashians or other loathsome cancers, as worthy concepts, but I have settled on the most sublime idea:
I would make pork bacon a healthy food
wow so many things need to be changed. No more wars, people harming animals, the filthy rich, get rid of all tv evangelist preachers. Pick your choice
Remove religions out of the human's life once forever!