healthy people could choose not to buy insurance — then sign up for it if they developed health problems later

Mandates and Mudslinging | By PAUL KRUGMAN | Published: November 30, 2007

From the beginning, advocates of universal health care were troubled by the incompleteness of Barack Obama’s plan, which unlike those of his Democratic rivals wouldn’t cover everyone. But they were willing to cut Mr. Obama slack on the issue, assuming that in the end he would do the right thing.
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The central question is whether there should be a health insurance “mandate” — a requirement that everyone sign up for health insurance, even if they don’t think they need it. The Edwards and Clinton plans have mandates; the Obama plan has one for children, but not for adults.

Why have a mandate? The whole point of a universal health insurance system is that everyone pays in, even if they’re currently healthy, and in return everyone has insurance coverage if and when they need it.

And it’s not just a matter of principle. As a practical matter, letting people opt out if they don’t feel like buying insurance would make insurance substantially more expensive for everyone else.

Here’s why: under the Obama plan, as it now stands, healthy people could choose not to buy insurance — then sign up for it if they developed health problems later. Insurance companies couldn’t turn them away, because Mr. Obama’s plan, like those of his rivals, requires that insurers offer the same policy to everyone. ...