What is so good about having an empire?

Answer 1

Some people liked empire because it gave them the opportunity to kill or abuse others with impunity. For most, though, it offers a means to shape other nations in a way that benefits yourself - until they decide they've had enough and kick you out, or until someone else steals your empire. Meanwhile you've expended tens of thousands of lives and billions of pounds/dollars/whatever on... well, on making sure that a bit more of what someone else produces ends up in your pocket. And then you realise that if you'd helped these people to get richer rather than skimming of as much of their surplus as you could get away with, they might now constitute a thriving export market rather than a basket-case economy. But by then it's too late, and you've nobody to export to but other rich countries who produce pretty much the same as you do and don't need or want that much of your produce. And then as if that wasn't bad enough, some of your former subjects have the nerve to start undoing the stagnation you presided over, and exporting into an international economy that you'd thrown open when you were top dog and best placed to exploit it. And because you'd kept them a low-wage economy for the sake of cheap raw materials, they can now undercut your own producers even at home.

All in all, it wasn't a particularly brilliant idea.