>The difference between Apple and Google is that Google is doing things which may not be desirable despite no law compelling them to.
No, the difference between Apple and Google is that Google decided to leave China rather than cooperate with the government.
>If the US government (or any other government) manages to pass a law which says that Apple must turn over all the user data they have - or that they must collect certain types of data, there is nothing Apple can do other than comply - or shut shop.
Shut shop? You mean like how Google shut shop?