In one case, an insurer prevented a woman from getting a CT scan her doctor ordered. In another, a mother couldn’t afford the full regimen of special bags needed to clear her cancer-stricken daughter’s lungs. In a third case, a woman lost her health insurance and could not afford end-of-life chemotherapy.

These examples come from National Nurses United, the country’s largest nurses’ union. To prevent further incidents like these, the union favors a universal, government-run health care system. A lead editorial in the New York Times last week appeared to endorse their thinking.

Here is what these folks are missing.

The events described and many more like them happen every day. In every country. All over the world. And more than 90 percent of the time, the insurer is the government. According to one report, one out of every six British cancer patients is denied access to the latest cancer drugs. That’s mainly because the British National Health Service has decided that the drugs are too costly relative to the gain.

So how does turning medical decisions over to government improve things? More often than not, it makes things worse.