What would happen if the individual mandate were removed from the health care bill? Republicans are proposing to do that but leave intact the rules on pre-existing conditions. This sounds like disaster because then the equilibrium is for only the already-sick to have “insurance,” meaning premiums are very high, meaning that the healthy prefer not to buy insurance until they are already sick.

This is not a problem of “skyrocketing costs” as some characterize it. If the same number of people get sick, then costs are the same. Its the premiums that skyrocket. The problem with that is that health care insurance is no longer insurance.

But the individual mandate is not the only way to bring the insurance back into health insurance. (And it appears that the penalties are so low that we are headed for this equilbirium anyway. See this article on MR. ) Many employer-based health insurance providers use a system of “open enrollment.” You can sign on to the plan when you join, but if you don’t and then decide later you want to , you must wait until a specific narrow window of time.

I don’t know what the intended purpose of open enrollment is but one effect it has is to give incentives to buy insurance before you get sick. A system like this would work just fine in place of the individual mandate.

Even better: when you turn 21 you are able to buy insurance from any provider regardless of your pre-existing conditions. This right continues as long as you have had insurance continuously. If you chose not to buy insurance in the past (and you could have afforded it) and you wish to buy it now then you cannot be denied coverage due to pre-existing condition. However, insurance companies are not required to offer you the same policy as the main pool.

Update: Austin Frakt argues that the penalties are already high enough to avoid the bad equilibrium.