News broke late last month that yet another of the nation’s largest health insurers, Aetna, is pulling out of state health exchanges in 2017. The company’s action marks the failure of every market-based reform included in the Affordable Care Act (ACA).

The insurers that remain in the exchanges find themselves with unprecedented leverage to demand double-digit premium increases next year, which will leave eleven million patients with few options. The collapse of policies designed to increase competition between health insurers should serve as a lesson in an election year when both candidates, Donald Trump and Hillary Clinton, have been running on the promise of even more such reforms.

The first market-based reform to collapse was the introduction of CO-OPs, new consumer-owned health insurers designed to compete with large commercial plans. Of the twenty-three CO-OPs launched for 2014, sixteen have already closed their doors or been shut down by state regulators. The CO-OPs failed in part because they expected government subsidies that never arrived, but more importantly they didn’t have the size or leverage to negotiate rates with large hospital and physician groups, paying more for the same patient care than the dominant insurers they were competing with.