The U.S. may not be Venezuela, but consider the Democratic agenda that is emerging from Congress and the party’s presidential contenders. You decide if the proposals meet the definition of socialism.

• Medicare for All. Bernie Sanders’ plan, which has been endorsed by 16 other Senators, would replace all private health insurance in the U.S. with a federally administered single-payer health-care program. Government would decide what care to deliver, which drugs to pay for, and how much to pay doctors and hospitals. Private insurance would be banned.

As Senator Kamala Harris put it recently on CNN, “the idea is that everyone gets access to medical care, and you don’t have to go through the process of going through an insurance company, having them give you approval, going through the paperwork, all of the delay that may require. Who of us has not had that situation, where you’ve got to wait for approval, and the doctor says, well, I don’t know if your insurance company is going to cover this? Let’s eliminate all of that. Let’s move on.”

If replacing private insurance with government control isn’t socialism, what is?

• The Green New Deal. This idea, endorsed by 40 House Democrats and several Democratic presidential candidates, would require that the U.S. be carbon neutral within 10 years. Non-carbon sources provide only 11% of U.S. energy today, so this would mean a complete remake of American electric power, transportation and manufacturing.

Oh, and as imagined by Rep. Alexandria Ocasio-Cortez, all of this would be planned by a Select Committee For a Green New Deal. Soviet five-year plans were more modest.

• A guaranteed government job for all. To assist in this 10-year transformation of society, the Green New Deal’s authors would “provide all members of our society, across all regions and all communities, the opportunity, training and education to be a full and equal participant in the transition, including through a job guarantee program to assure a living wage job to every person who wants one.”

• Vastly higher taxes. These ideas would require much more government revenue, and Democrats are eagerly proposing ways to raise it. Mr. Sanders wants to raise the top death tax rate to 77%. Ms. Ocasio-Cortez wants a new 70% tax rate on high incomes, which is supported by the Democratic intelligentsia. The House Ways and Means Committee is working on a plan to raise the payroll tax to 14.8% from 12.4% on incomes above $400,000.

Never to be outdone on the left, Ms. Warren wants a new 2% “wealth tax” on assets above $50 million and 3% above $1 billion, including assets held abroad. France recently junked its wealth tax because it was so counterproductive, and such a tax has never been levied in America. This is government confiscation merely because someone has earned or saved more money than someone else. Socialism?

These are merely the most prominent proposals. There are many others, such as Ms. Warren’s plan to set up a government-owned generic drug maker that would inevitably put private companies out of business because its cost of capital would be zero.

Some readers might think this is all so extreme it could never happen. But presidential candidates don’t propose ideas they think will hurt them politically. The leftward lurch of Democratic voters, especially the young, means the party could nominate the most left-wing presidential candidate in U.S. history. If other Democratic candidates oppose any or all of this, we’d like to hear them.

The American public deserves to have a debate about all this, lest it sleepwalk into a socialist future it doesn’t want. Credit to Mr. Trump for teeing it up.