The Swoop!

It's a very short novel. A faithful Boy Scout, Clarence is one of those kids who are worried a lot about their country - even too much. He is from a nice staid family who think he's a little nuts, because of his constant groans about how England has deteriorated. But it seems that he might be at least partly right when German prince invades during tea. Nine other hostile armies invade England, much to the indignation of the populace. Unfortunately, the English don't put up much of a resistance,