It’s internally inconsistent.
If they can’t COMPEL you to buy something, how can they rationally PENALIZE you for not buying it?
Makes zero difference if it’s called a tax or a fine or a co-pay, it’s still a penalty that treats some people (those who don’t buy insurance) different from those who do.
So there are due process and equal protection problems also.
If they can’t COMPEL you to buy something, how can they rationally PENALIZE you for not buying it?
Exactly! I pointed this out a couple times on other threads. If the states can't be compelled into Medicaid expansion by threats of withholding funding, then how can citizens be taxed if they don't opt into health insurance? Sure, in the first instance, the feds can't withhold something already promised, but in the second, it implies additional penalties for the option of doing nothing. Neither, IMO, is constitutional.