When he talks about his efforts to repeal the Affordable Care Act, President Trump almost always asserts that Obamacare is “exploding.” Republican members of Congress make similar claims, insisting that Obamacare is unsustainable—and that they therefore have no choice but to “repeal and replace” it.

There is some basis for this argument. More than 1,300 counties only have one insurer in their exchanges, meaning there is no competition. But there is a nuance that Republicans willfully ignore: This is a problem of their own creation that is largely confined to red states.