Why does ERISA preemption matter in the health insurance context, and why do many people think it should preclude state health insurance mandates, such as the Wal-Mart law already deemed preempted in Maryland and the San Francisco ordinance that is currently the subject of litigation over the question? Leaving aside the legal reasons why the acts are preempted, it is because employers, who provide most of the health benefits in the country, rely upon the stability and predictability generated by ERISA and the preemption doctrine. That, in any event, I think is a fair reading of this article here.