Few have ever heard of “Health Reimbursement Accounts,” but they could fundamentally change the nation’s health care system — for the better — and destroy the Democrats’ case for socialized health care. Late last week, the Trump administration finalized rules that will let companies put money into tax-exempt HRAs that their employees could then used to buy an individual insurance plan on their own. Seems like no big deal, right? Except it will start to unravel a 77-year-old policy mistake that is largely responsible for many of the problems the health care system suffers today. Back in 1942, the Roosevelt...