As this week’s jousting between Speaker Paul Ryan and the Freedom Caucus makes clear, the Republican Party’s conservative and pragmatic wings don’t always agree. But there’s consensus on this: The American Health Care Act, the GOP’s bill to repeal and replace ObamaCare, doesn’t do enough to make insurance more affordable.

Here’s how Sen. Ted Cruz and Rep. Mark Meadows put it last week in this newspaper’s online edition: “First, we must lower insurance premiums. Nothing matters more. The current House bill would not achieve...