I don't understand what you're getting at. If a US citizen broke my window (i live in the UK), i'd report it to the police and the criminal would be subject to

I don't understand what you're getting at. If a US citizen broke my window (i live in the UK), i'd report it to the police and the criminal would be subject to UK law at all times while here (unless he has diplomatic immunity or something). What does that have to do anything with your 2nd point? Do you mean "sue", or do you really mean "use" like you wrote? If you meant sue, then of course we can, Google has a presence in the UK and thus is subject to UK law (not saying all of Google might be subject to UK law, but at least its UK arm).