We're also the only developed country that relies on for-profit insurance companies for basic medical insurance.
The Netherlands aren't a developed country now? News to me.
We definitely have mandatory health insurance over here. You get to pick your insurance company, but you have to pick one. The companies have to provide certain minimum coverage and can't discriminate based on age or health (but they get compensated by the government for having to take on riskier clients).
The system seems to work quite well AFAICT.