“Medicare for all” is another name for socialized health insurance. The Congressional Budget Office published a paper on the general idea this week, reigniting debates over the costs.

Follow the defenses of “Medicare for all” closely enough, through their twists and turns, and eventually you end up in a dead-end alley from which there is no escape. Democrats’ plans to supposedly open up Medicare to everybody always end up in the same place: They absolutely must bar people from choosing to buy their own insurance instead.

The winding debate goes like this: Conservatives point out that turning the federal government into a massive health insurer for all Americans would increase federal spending by $32 trillion.

Socialists respond that, in fact, socializing health insurance will save Americans money because it will reduce the combined amount spent on healthcare by government, individuals, and private insurance.

How would that work? Well, recall what Democrats were calling socialized health insurance before they settled on the brand name of “Medicare for all”: Single-payer healthcare. This is what economists call a "monopsony": When there is only one buyer of goods, he has a disproportionate power over prices, as multiple sellers must compete for his business.

This monopsony power is where the socialists hope to find savings. Single-payer healthcare can drive profit margins of healthcare providers — doctors, hospitals, drug companies, device makers, nurses — down to nearly zero.

But what if an independent family doctor, who lacks the economies of scale that bigger practices enjoy, bristles at Uncle Sam’s lower payments and opts instead to deal only with folks on private insurance? If any serious number of practitioners does this, then suddenly we’ve got exactly the thing the socialists were trying to prevent: competition! Without monopsony power, the government can’t unilaterally set prices in healthcare.

This is why the most popular versions of “Medicare for all,” sponsored by Sen. Bernie Sanders, I-Vt., and Rep. Pramila Jayapal, D-Wash., would prohibit private health insurance that competes with the government's insurance. They want to run not only health insurance but the entire healthcare sector.

This means they would also strip millions of Americans of their current healthcare plans.

We've seen this one before. Once again, the socialist journey that begins with laudable goals of standing up to big business and looking out for the poor ends up in the dark alley of government control with no individual choice.

Control over healthcare isn’t merely about controlling spending, controlling doctors, and controlling nurses. It’s also about controlling one of the most intimate aspects of our lives. When Uncle Sam is paying your bill, he also gets to tell you what to eat. Or when to stop having children. Or when Grandma has lived long enough. And so on and so forth.

So yes, it’s good to follow the money trail of "Medicare for all," not because the money matters most, but because it leads us to the true cost, which is the loss of freedom.