Insanity?

I think that Claudius honestly thinks that Hamlet is on drugs, crazy, whatever you call it. King Claudius spends more time worring about Hamlet and trying to figure out if he is insane, then he spends with any other problem, such as the "international problems" with fortenbra... (i dont know how thats spelled)- he wrote those off and was more freaked out about hamlet. He also is putting so much time and energy into the matter, with the whole friends sent to spy and check up on him. If he thought it was all a joke, or an act, he wouldnt be wasting his time on Hamlet. Its not like he cares for the guy anyway. He's gotta be believeing this insanity act.