How many armies

How many armies does it take to change a light bulb?

At least six: 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 run away;: the English to stand firm back home but not get anywhere near the bulb; the Americans to turn up late, finish it off and take all the credit; and the Swiss to pretend nothing out of the ordinary is happening.