When Congress passed and the president signed the Affordable Care Act, supporters of the law were adamant that Obamacare would control health costs in government health care programs. It hasn't worked out that way, of course, and particularly in Medicaid, the costs of the program are exploding in ways that states had not predicted and did not plan for.

In Kentucky, for example, enrollments during the 2014 fiscal year were more than double the number projected, with almost 311,000 newly eligible residents signing up. That's greater than what was initially predicted through 2021. As a result, the state revised its Medicaid cost estimate from $33 million to $74 million for the 2017 fiscal year. By 2021, those costs could climb to a projected $363 million.

"That is a monstrous hole that we have got to figure out how to plug, and we don't know how to do it," said Kentucky state Sen. Chris McDaniel, a Republican who leads the Senate budget committee and opposed expansion. "The two biggest things that keep me up at night are state pensions and the cost of expanded Medicaid."

It's a similar story in many expansion states. In California, actual enrollees tripled projected Medicaid enrollment. In Ohio, costs have more than doubled.

Even in a non-expansion state like Missouri, current enrollment in the Medicaid program has grown so much that today nearly one in seven Missourians is in a government health care program. Between May 2014 and May 2015, over 100,000 currently eligible enrollees were added to the state's Medicaid program, thanks in part to the woodwork effect we've often talked about.

Missouri's Medicaid program needs to be significantly reformed not only for patients and taxpayers, but also for other programs in the state budget. In Kentucky, the state senator quoted in the story said that pensions and the cost of expanded Medicaid kept him up at night, but even unexpanded and unreformed Medicaid presents a serious threat to the solvency of other big-ticket programs in Missouri—including education. We have presented a variety of reforms that can help get Medicaid's problems under control so that the state won't have to pit the interests of children against Medicaid patients.

But unfortunately, it seems the pro-Obamacare crowd wants to make fixing Medicaid contingent on simultaneously detonating a fiscal bomb in the state budget with an expansion . . . and that's a non-starter for supporters of good government. Policymakers should recognize the mistakes other states have made in expanding their broken Medicaid programs and decline to emulate their poor decisions. It's time for Medicaid reform in Missouri, period.