Have you noticed how often conservatives who disagree with a policy proposal call it a “job killer?”

They're especially incensed about proposals to raise the federal minimum wage. They claim it will force employers to lay off workers worth hiring at the current federal minimum of $7.25 an hour but not at a higher minimum.

But as Princeton University economist Alan Krueger pointed out recently in the New York Times, “research suggests that a minimum wage set as high as $12 an hour will do more good than harm for low-wage workers.”

That's because a higher minimum puts more money into the pockets of people who will spend it, mostly in the local economy. That spending encourages businesses to hire more workers.

Which is why many economists, like Krueger, support raising the federal minimum to $12 an hour.

What about $15 an hour? 

Across America, workers at fast-food and big-box retail establishments are striking for $15. Some cities are already moving toward this goal. Bernie Sanders is advocating it. A national movement is growing for a $15 an hour minimum.

Yet economists are nervous. Krueger pointed out a $15 an hour minimum would “put us in uncharted waters, and risk undesirable and unintended consequences” of job loss.

Yet maybe some jobs are worth risking if a strong moral case can be made for a $15 minimum.

That moral case is that no one should be working full time and still remain in poverty.

People who work full time are fulfilling their most basic social responsibility. As such, they should earn enough to live on.

A full-time worker with two kids needs at least $30,135 this year to be safely out of poverty. That's $15 an hour for a forty-hour workweek. 

Any amount below this usually requires government make up the shortfall – using tax payments from the rest of us to finance food stamps, Medicaid, housing assistance, and other kinds of help.