Why can’t Republicans be more like Democrats?

When the Democrats passed Obamacare, they never even once argued about how it would work. They only talked about who was going to benefit and how—at least in public.

Republicans, by contrast, are bogged down in a hopelessly complicated debate over what to do about pre-existing conditions. And their focus is on something that is very uncharacteristic: regulation. Why aren’t they instead focused on markets?