One reason people hate war is because it's extremely expensive. The British spent lots and lots of money on the war, so much that they eventually went into debt. After the war ended, they began to tax the colonies so that they could pay off their debt because they were in such a horrible financial situation! The French and Indian war really did lead to the American Revolution.
The best answer to put here as a direct consequence would be it put the British in a lot of debt.
In the era after Wold War I and before the Great Depression, American towns grew rapidly mostly because of the Second Industrial Revolution, which gave way to a rise of factories both in and around major cities in the US.