House Republicans want to pass a bill delaying Obamacare’s 40% excise tax on high-cost employer plans—the “Cadillac tax”—by another year, to 2023. GOP hostility to this tax is a mistake. Capping the tax break for job-based insurance is essential for a market-based approach to cost control. The federal government heavily subsidizes every extra dollar spent on job-based insurance, which undermines the incentive for employers and workers to seek out lower-cost options. Some Republicans believe they can kill the Cadillac tax and replace it later with a better alternative. That’s wishful thinking. If Congress keeps delaying the tax and eventually kills it, there will be no appetite to impose a different version of the same policy.

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