As a UK citizen I am now subject to three or possibly four sets of laws
UK law(and it's variant if I travel to Scotland or do business there, Scots law) EU law and now US law.
UK law is all well and good, I was born and brought up here so I have a pretty good idea of what I can and cannot do. (Scotland has roughly the same criminal law but a different civil law system I think)
EU laws, which generally have something to do with commerce, are not too bad as to have any effect on me they have to be translated into English law, usually with all sorts of unnecessary add-ons and gold plating. Just occasionally the prats in Whitehall will get slapped for some fundamental human rights violation which is OK by me.:-)
Just as an aside, a lawer friend once explained to me that in its simplest form UK law generally says 'What isn't forbidden is allowed'. But that Continental (EU) law says 'Everything is forbidden except for what is allowed'. He followed on from this to say that 2 things stemmed from this, in the UK what is forbidden rises over time, but in Continental (EU) Law what is allowed rises.
and now to US law, which seems fundamentally different from most other jurisdictions and seems to apply, regardless of UK law, whenever I travel, do business, or go online. If I break that I can now be shipped off to the US for trial as a non-person/terrorist/someone whose annoyed a US business.
I like to think that if the last ever applied I'd behave like any true US citizen " You can ship me off to your godforsaken country over Your dead body!'
Good luck on keeping track of what laws you break!