Conclusion

As you can see, molecules have had an enormous impact on the course of human events.  Even the slightest chemical change or property can have a major effect on the world.  Many of the stories in the book reflect this idea, which I feel is also epitomized in the old English nursery rhyme:

For the want of a nail the shoe was lost.
For the want of a shoe the horse was lost.
For the want of a horse the rider was lost.
For the want of a rider the battle was lost.
For the want of a battle the kingdom was lost.
And all for the want of a horse-shoe nail.

I hope you've enjoyed learning about the stories in Napoleon's Buttons: 17 Molecules That Changed History!