It’s always a bit hard to know exactly what conservatives are trying to claim when they say that the “individual mandate” element of the Affordable Care Act is unconstitutional. Do they mean they think it’s unconstitutional in light of the actually existing state of American law? Or do they mean it’s unconstitutional in the sense that “were we to interpret the constitution in a totally different way, one of the many upshots of that would be to deem the individual mandate unconstitutional.”
But viewed either way, what people need to see about the mandate is that it’s just a form of tax. I could say “in addition to their other income taxes, everyone needs to pay a $X annual ‘health responsibility tax.’” Then I could also adopt a legal definition of adequate health insurance, and say “everyone who has adequate health insurance gets a $X tax credit.” Wham, bam, mandate.
The point is that it’s not like the Gestapo is going to be showing up at your house to arrest the uninsured. The idea is to ensure that everyone is making a financial contribution to the overall pooling of risk, either by paying a tax/fine/fee or else by purchasing health insurance and thus broadening the spread of risk. Now I’ll be the first to agree that this is a mighty clunky way of achieving a nationwide risk pool — the alternative of just taxing everyone and then having the government give everyone health insurance benefits seems a lot simpler and better.