ObamaCare’s image of invincibility is increasingly being exposed as a political illusion, at least for those with permission to be honest about the evidence. Witness the heretofore unknown phenomenon of a “free” entitlement that its beneficiaries can’t afford or don’t want.

This month the Health and Human Services Department dramatically discounted its internal estimate of how many people will join the state insurance exchanges in 2016. There are about 9.1 million enrollees today, and the consensus estimate—by the Congressional...