For those who dream of universal health care, Washington State looks like a pioneer. As Gov. Jay Inslee pointed out in the first Democratic presidential debate on Wednesday, his state has created the country’s first “public option” — a government-run health plan that would compete with private insurance.

Ten years ago, the idea of a public option was so contentious that Obamacare became law only after the concept was discarded. Now it’s gaining support again, particularly among Democratic candidates like Joe Biden who see it as a more moderate alternative to a Bernie Sanders-style “Medicare for all.”

New Mexico and Colorado are exploring whether they can move faster than Congress and also introduce state-level, public health coverage open to all residents.

But a closer look at the Washington public option signed into law last month, and how it was watered down for passage, is a reminder of why the idea ultimately failed to make it into the Affordable Care Act and gives a preview of the tricky politics of extending the government’s reach into health care.