At this point, technology has enabled this sort of behavior at mass scale, now revealing far more personal and useful information about individuals.
A feasible model to work from may be go look at the healthcare industry and HIPPA requirements/liabilities and adapt as needed. Certainly not perfect but it's a good starting point for widespread data laws.
The question is, will our representatives actually give teeth to real data protection legislation (not a facade with no teeth only enacted by name) in the US or are they too deeply in bed with industry that they'll protect business rights over real people who suffer real direct damages.