Why is the public option so vitally important to health reform?At the broadest possible level, the public option is necessary simply because it's impossible to identify a successful health system anywhere in the world based on a for-profit insurance model. If profit-driven health insurance could be made to work, then surely somebody would have figured it out by now. Paul Krugman, in an Aug. 17 New York Times column, likens health reform to the reforms Switzerland instituted in 1994: "[E]veryone is required to buy insurance, insurers can't discriminate based on medical history or pre-existing conditions, and lower-income citizens get government help in paying for their policies." But there's a significant difference. In Switzerland, private insurers are required to provide basic health coverage on a nonprofit basis. Under Obamacare, private insurers will continue to seek profits, and it's quite possible that the new regulatory restraints imposed on them (take all comers, don't punish the sick with higher premiums, don't seek out fine-print reasons to cancel policies after policyholders get sick, etc.) will inspire them to find ever-more-ingenious ways to avoid payouts. President Obama often says that a public option will help keep the private insurers honest. What he doesn't say, but surely knows, is that private insurers' duties to their shareholders may be irreconcilable with their duties to their customers.