Ok, but realistically, the people who would actually attempt tax evasion here wouldn't be susceptible to any of the above.
Let's assume a scenario where you have a dual citizen of the US and a South American country that has less than stellar relations with the US government.
Let's say they obtained their US citizenship by being born in the country during a temporary period of time that the parents resided there. The family decided to move back after a year or two, another 40 years passed, and the kid has grown to be a successful plastic surgeon who runs a self owned clinic and earns $200k income annually. Being aware of their dual citizenship they keep their wealth invested in entities with no US presence and never self-report anything to the IRS.
This is where I am not seeing any way for the IRS to enforce or do anything about this type of tax evasion.
Could you give me a name, or at least some link to a government website that describes the system you're talking about?