So, lets say for example that the US requires that you keep data on customers so that law enforcement can use it, but the EU requires that you don't so that privacy is protected.

Are you are suggesting that one of those laws should be changed to make it easier for multinational companies to operate, even though there was a good reason for the law in the first place? Because I would say that if the company absolutely has to keep customer data then they shouldn't operate in a country where that is illegal, and if they refuse to keep customer data then they shouldn't be operating in the country where it is required.