American War of Independence..... bring along a few M1 tanks and Great Britain'd still rule supreme over North America. Oh, and not to forget; wipe out Japan so you can have a nice country estate.
And of course eliminate France. What's France good for anyways, except wine, baguettes and Alneyan?
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O'Neill: I have something I want to confess you. The name's not Kirk. It's Skywalker. Luke Skywalker. -Stargate SG1