Late last year, when conservatives everywhere were grieving publicly for each American who’d received a cancellation notice from a health insurance carrier, the smartest among them realized they had a small problem on their hands.

The wave of cancellations made for great politics, and it was a joy to watch the public’s trust in Obama crater for having promised everyone that they could keep their plans. But by turning an insurance market disruption into a political liability — and a normatively bad thing — Republicans had left themselves very little room to advance conservative health policy ideas.

The cornerstone of nearly every conservative health care reform plan is to eliminate or dramatically reduce the tax preference for employer-sponsored health insurance and use the revenues to help people pay for their own coverage. But the disruptions that would entail would dwarf the ones Obamacare is creating, and conservative wonks realized that by opportunistically attacking Obamacare, political operatives had just crafted the very attacks that could ultimately doom their own policymaking pursuits.

Writing at National Review late last year, Ramesh Ponnuru noted that in the wake of the cancelations row conservatives would have to move more gradually than they might ideally like.

“Some Republican health-care plans would run up against this same obstacle, because they, too, disrupt existing health-insurance arrangements,” he wrote. “The answer to this problem, I think, is not to abandon the idea of moving in the direction of free-market health care as an alternative to Obamacare; it’s to make that move in steps. Step one would be flattening the tax break so it no longer rewards the purchase of the most comprehensive coverage available.”

Easier said than done. Two weeks ago a trio of Republican senators introduced a plan to replace Obamacare. Conservatives everywhere, including Ponnuru and his National Review colleagues, applauded it. But its authors will seemingly have to choose between actually financing it or inviting the same severe market disruptions the GOP is now on record opposing. The plan itself called, somewhat confusingly, for “cap[ping] the tax exclusion for employee’s health coverage at 65 percent of an average plan’s costs.” Yuval Levin surmised reasonably that they meant capping it at the 65th percentile of employer plans. But either way its authors became caught in the trap their own party set for them in the fall. When questions started rolling in about market disruptions, they made a dramatic change to their white paper. The cap would now be set, vaguely, at “65 percent of the average market price for an expensive high-option plan,” presumably at the expense of revenues required to finance the plan’s coverage goals.