ObamaCare’s “Millennial mandate,” the requirement that employers who offer health coverage for employees’ dependents continue to offer such coverage until the dependents turn 26 years old, is one of those supposed free lunches.

This mandate’s benefits unquestionably come at a cost. Expanding health insurance coverage among adults age 19-26 leads them to consume more medical care. When those people file insurance claims, health-insurance premiums rise. Yet ObamaCare does an amazing job of hiding those costs from voters.

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