If we could engineer a chemical agent that forces people to love each other, couldn't we end all armed conflict right then and there?
Also, love probably wouldn't work as well as one might think. People who love each other end up in violent conflict all the time, just ask any cop.
I think you're looking for a "mutual respect and acceptance bomb".
I suspect that a large portion of the conflict between people who "love" each other is because one wants the other to be different.