I think it is a good idea to look back and see what patents actually were intended for.
When the patents weren't there, the inventor carefully guarded its knowledge and this knowledge was lost to the public. The patent was a method of encouraging the inventor to share the knowledge with community. "Describe us your invention, and for this we will grant you a few years of monopoly on it; after that the invention becomes public domain". This benefits both the inventor (who has monopoly then) and the community (who will eventually have details enabling to easily recreate the invention).
What is wrong is that in the US (and Japan) patent system changed into something completely different. Fortunately the rest of the world is mostly true to the original spirit of patents though.
Oh, and outside US patents must be non-obvious, patent must describe the invention in detail (so it can be recreated easily), and ideas, mathematical forumlas, algorithms and business models are of course not patentable.
To sum up: patent is for making sure that invention (something non-obvious, ingenious) will end up in the public domain (and not something to fight high unemployment of lawers and judges).