The Affordable Care Act's expansion of Medicaid eligibility hasn't been universal.

Medicaid is the federal-state health care program for Americans that historically focused on pregnant women, children, seniors and the disabled.

President Obama's namesake health care law expanded Medicaid eligibility to all adults under age 65 with incomes up to 133 percent of the federal poverty level. Under the law, states were essentially required to expand eligibility or risk losing federal funding to their existing programs.

But following a rather complicated 2012 Supreme Court decision, Medicaid expansion became optional. As of Dec. 1, 2016, 19 states so far have refused the expansion.

"I don't think anyone anticipated when the law was written that states would have the opportunity to opt-out of the Medicaid expansion," Christine Eibner, senior economist at the Rand Corporation, told us in 2015. "That's a major departure from the law's initial intent."

In states that are not participating, coverage is generally capped for those with children who have incomes at 44 percent of poverty (about $8,870 a year for a family of three) while childless adults remain ineligible in nearly all of them. According the Kaiser Family Foundation, that amounts to a coverage gap of 2.6 million people.

Obama tried to achieve this goal, but the Supreme Court curtailed complete implementation. We rate this a Compromise.