President Obama's health care overhaul had a rough day before the Supreme Court on Tuesday, with the conservative majority signaling that it's leaning toward striking down the law's key individual mandate. On Wednesday, the last of three days of the high court's ObamaCare arguments, justices will once again focus on the mandate that nearly all Americans obtain health insurance. They'll weigh the issue of "severability" — essentially, if the court throws out the mandate, can the rest of the law stand? The conventional wisdom has long been that ObamaCare needs the mandate, since it would be impossible to cover the costs of everyone's health care unless everyone is forced to buy insurance. But a new study from the Urban Institute suggests that the largely toothless mandate isn't really that big a deal, since only about 3 percent of Americans would even be subjected to it, and several states are working up their own Plan B if the mandate goes down. Could ObamaCare really survive without the individual mandate?

No. ObamaCare is a package deal: "The only way to push toward universal coverage via private health plans is to have a mandate that gets everyone in the pool," says Matt Miller at The Washington Post. "This is Insurance 101": If ObamaCare bars insurers from turning people away, and the Supreme Court allows healthy people to shun insurance until they're sick, "the system implodes in a spiral of accelerating premiums." Bottom line: No mandate, no ObamaCare.
"Anxiety over the individual mandate"

Striking the mandate would cripple, not kill, the law: ObamaCare's other provisions "might — that's 'might,' not 'would' — be enough to stabilize the [insurance] market" so that, even without the mandate, a lot of people would be better off than they are now, says Jonathan Cohn in The New Republic. ObamaCare's subsidies, for instance, would make health insurance more appealing for people who would otherwise turn it down. Of course, this would "fall short of the nearly universal coverage that the Affordable Care Act is supposed to achieve." But while striking down the mandate "would be a breathtaking act of judicial arrogance, damaging to the country's well-being and to its delicate balance of governing powers," ObamaCare could still "survive in some form."
"Let's all take a moment to breathe, OK?"

Actually, the mandate can be replaced: The individual mandate is the most "elegant" and effective way to make ObamaCare work, but it isn't the only path, says Ryan Lizza at The New Yorker. The government could auto-enroll people in health plans with an opt-out, or use incentives, or let the states figure it out. So unless the court kills the whole law, the bulk of ObamaCare — "the new insurance exchanges, the subsidies for low-income individuals to buy insurance, and most of the insurance-market regulations — can survive," even if the mandate doesn't.
"What if the mandate goes down?"