Why can't Europe defend itself?

[Sasaki Kojiro]

Britain's and France's empire were much larger then Germany's at the beginning of WW1 and they certainly spent more effort in making and maintaining an empire abroad then Germany did. Why did Germany lose?

Not attacking you, just putting forth questions popping in my head. Which is why I should probably read about it before commenting.

Why was Germany able to compete at all? Because they invested more at home? Wasn't one of the causes of the American Revolution the fact that parliament was trying to actually get some money out of the colonies? I have to think the British profited a lot from India though...