Armies change a lightbulb

Question: How many armies does it take to change a lightbulb?

Answer: At least five. The Germans to start it, the French to give up really easily after only trying for a little while, the Italians to make a start, get nowhere, and then try again from the other side, the Americans to turn up late and finish it off and take all the credit, and the Swiss to pretend nothing out of the ordinary is happening.