Like most things in life and certainly in health care, the devil is in the details of Republicans’ American Health Care Act.

So when Rep. Cathy McMorris Rodgers (R-Wash.) wrote an op-ed in The Washington Post explaining that her son Cole, born with Down syndrome, was at the heart of her support for the bill, the devil probably did a little happy dance.

Though McMorris Rodgers wrote that the GOP bill would still protect people with pre-existing conditions like her son, the reality is that she doesn’t really know how they’ll be affected. None of us do.

But one glimpse at recent history might indicate which way things will go.

The Republican bill to replace the Affordable Care Act, otherwise known as Obamacare, shifts decision-making to the states. Without a sense of what individual states intend to do, we can’t really make any declarations.

Obamacare mandated that everyone have health insurance or pay a penalty. This pushed the young and healthy into purchasing plans, which in turn helped offset insurance costs for the not-so-young and not-so-healthy. Obamacare also forbids insurers from charging those with expensive medical conditions more than they charge other consumers in the general insurance pool.

Before the Affordable Care Act became law, people with chronic diseases paid several times as much for health insurance — if they could even find an insurer to cover them. Can you imagine facing cancer treatment without health insurance?

The GOP plan isn’t quite dropping the mandate that everyone have health insurance. Republican leaders just settled on getting rid of the penalty for not doing so, instead letting insurers tack on a one-year 30 percent surcharge for any coverage gaps.

Power shifts to the states.

But here’s where the wicket gets sticky: An amendment added last week by Rep. Tom MacArthur (R-N.J.) says individual states can obtain a waiver from the Health and Human Services Department. With that waiver in place, people who allow their coverage to lapse would be subject to higher premiums for pre-existing conditions.

Health experts say that would lead to a sharp rise in premiums for those with medical problems. Karen Pollitz, a senior fellow at the Kaiser Family Foundation, predicts that people with pre-existing conditions would likely be priced out of coverage.

“To actually protect someone with a pre-existing condition,” she told ABC News, “they need full protection. Otherwise, it’s like giving someone half a bulletproof vest.”

Rodgers’ colleagues ― Reps. Fred Upton (R-Mich.) and Billy Long (R-Mo.) ― tried to sweeten the pot and mitigate some of the effects the MacArthur amendment would have on those with long-standing medical conditions. They threw in a measure to provide $8 billion to help these patients pay for increased premiums and out-of-pocket costs. The money would be spread among the states that decide to let insurers return to the practice of charging higher rates to certain customers.

High-risk pools didn’t work before.

As part of a waiver application to HHS, a state would be required to include a “risk-sharing plan” or to design a subsidy program for residents with pre-existing conditions.

Rodgers thinks this will be enough to protect people like her son. But that simply ignores history and the fact that the “high-risk pools” people with pre-existing conditions will be placed in under the GOP plan were uniformly considered disasters before Obamacare came along.

Even the high-risk pool in California, a state that would seem perfectly situated for success because of its huge economy, extensive medical care system and powerful advocates, failed. Before Obamacare kicked in, nearly 20 percent of Californians ― 6 million people ― lacked health coverage. Today, the state’s uninsured rate is under 9 percent, thanks to the Affordable Care Act.

High-risk pools just didn’t work, Richard Figueroa, who was the enrollment director of California’s high-risk pool, told the Los Angeles Times. He said he still shudders remembering some of the calls he had to field.

There were desperate callers pleading to get off the waiting list as cancer or other illnesses worsened, he told the Times. The most heart-wrenching were the quiet, polite calls from those who’d received a letter that a sick relative could finally get on the plan. “They would say, ‘Thank you, but you can give our slot to someone else, because my brother or my wife or my daughter has died,’” Figueroa recalled.

Things were no better in McMorris Rodgers’ home state of Washington, where more than 80 percent of the people referred to the state’s high-risk pool never got health insurance, according to Mike Kreidler, the state’s insurance commissioner, speaking to The New York Times.

California’s high-risk pool — like similar overstretched state plans around the country — became obsolete when the Affordable Care Act established the current federal system to guarantee coverage to Americans even if they’re sick.

So when McMorris Rodgers says, “States know better than the federal government how to allocate and manage resources to address the needs of their people. Our plan allows states to serve and provide financial support directly to vulnerable populations, including people with preexisting conditions” ― we just wonder which state she plans on moving to.