So the Democrats, after opposing Donald Trump in the 2016 election partly out of what they claimed was concern about his incivility and coarseness, are now pursuing a debate about health care legislation in Washington by characterizing the Republicans who disagree with them about policy details as mass murderers.

Think that's an exaggeration?

Hillary Clinton, the Democratic Party's 2016 presidential candidate who remains among its most prominent and mainstream voices, tweeted Friday: "If Republicans pass this bill, they're the death party."

Sen. Elizabeth Warren (D-Massachusetts) tweeted, "I've read the Republican 'health care' bill. This is blood money. They're paying for tax cuts with American lives."

Ezra Levin, an influential Washington organizer of the resistance to Trump, tweeted Sunday, "TrumpCare will kill tens of thousands of working class people, and with the savings it cuts taxes for billionaires."

This line of argument carries a powerful emotional charge. It isn't, though, a particularly useful, constructive, or clear-minded way to think or talk about writing laws.

To start with, there's the Washington-centric misconception that the killers are the congressmen. Disregarded are any other actors who play roles in our health care system. If federal politicians are murderers for adjusting health care laws, what about all the state-level politicians who failed to enact Mitt Romney-style comprehensive coverage in their own states before Obamacare? Were they also murderers for failing to act? What about doctors and hospitals who refuse to treat non-emergency patients who are uninsured and can't pay? The system could probably treat more people if doctors, nurses, and medical-device and drug-company executives earned less money. Does that make every BMW-driving surgeon a murderer? Is every individual American a murderer who spends any discretionary income on movies or trips to Disney World rather than charitable donations earmarked for uncompensated care to his local hospital?

It may well be that as a moral matter, voluntarily paying for a poor person's health care is a superior use of money than driving a fancy car or taking an expensive vacation. But an individual's choice to consume rather than donate doesn't make that individual a murderer, or even a killer. Neither does a congressman's decision not to compel the individual, by taxing him, to do so. The failure of Democrats to recognize this signals a fundamental confusion.

There's also a false certainty in the claim that higher taxes for more health insurance will translate into extended lives. Some of the more honest Democrats acknowledge this if one listens to them carefully. Even Sen. Bernie Sanders, for example, in repeating an exaggerated claim that TrumpCare would cause 28,000 unnecessary deaths, conceded, "Nobody, obviously, knows exactly what would happen."

Obviously.

The "Harvard" study—really more of a blog post by one Harvard professor, two non-Harvard medical students, and two scholars at a liberal think-tank—that Sanders and Clinton cite is more nuanced than they claim. It mentions two studies—"outlier results"—raising doubts about whether insurance coverage translated into better health. It concedes, accurately, "insurance is a necessary but not sufficient factor to receive quality health care." Ironically, its model for projecting what it calls "excess deaths" is based entirely on extrapolation from "analyses of the Massachusetts health reform." Again, that is a state-level reform of the sort that might have spread organically and successfully if President Obama and the Democrats in Congress hadn't decided to impose it nationally.

Democratic accusations about additional deaths are often made without any price tag attached. Assume, for the moment, that Democrats are right that money should be taken away from higher earners and redistributed instead for the purpose of extending life-years or improving health.

There's a whole universe of possible interventions other than subsidizing heath insurance or Medicaid. Auto-ignition breathalyzers to prevent drunk-driving accidents, a nationwide 55-mile-an-hour speed limit with aggressive enforcement, disabling texting from cellphones in moving cars, some sort of intervention in Syria—all might, at least potentially, save more lives at a lower cost.

Failing to enact these measures doesn't make politicians murderers, or even the moral equivalent of murderers. It's just a political difference of opinion.