David French of National Review Online cautions progressives to be careful what they wish for when it comes to health care reform.

Bernie Sanders is introducing the Medicare for All Act of 2017, and this time he’s no lone socialist crying in the progressive wilderness. A total of 15 Democratic senators are backing his bill, including most of the top Democratic contenders for the presidency. …

… Sober-minded Democrats should be terrified. They just might be handing Trump two terms. …

… First, and most obviously, single-payer health care comes with an extraordinary tax bill. The very instant voters saw their take-home pay plunge — often by an amount that far exceeds their traditional employee contribution to their employer-provided insurance — they would realize that “free” health care isn’t free. …

… But the reasons why the single-payer push helps Trump and the GOP go well beyond the health-care debate itself. This emerging litmus test is symptomatic of a larger problem: The Democratic party is increasingly the wholly owned subsidiary of the progressive base, and the progressive base has become too radical for widespread electoral success.

Here, the results speak for themselves. President Obama’s personal popularity obscured the unpopularity of his policies, and the Democrats have steadily collapsed as a national political party. Its appeal is concentrated in densely populated coastal urban enclaves, and it keeps generating political ideas that appeal primarily to this urban base — and no one else.