Not sure you can change the World ! The person who said the pen is mightier than the sword was obviously a long way away from the pointy end !
But I would like to think that a good writer can bring about every emotional state from tears to laughter.
I read a Second World War story many, many years ago about a group of guys brought together in Boot Camp. The author spent a lot of time introducing us to all the key characters and he did it so well they almost became friends. As the story progressed we the reader sweated and suffered with them as they went through the hell of training.
Laughed at their jokes, shared their dreams and were proud of them as the past out and became a true fighting unit.
Then they went off to war in the Pacific....and then they started to die !
Yeah.... I had more than a lump in my throat as it happened.
The story was pure fiction but the autor knew his craft and as he killed off the characters it was like losing a friend.
Now that's writing !