It’s a war. It’s playing favorites. It’s harmful and divisive. Conservatives have heard President Obama’s proposal to increase the Child Tax Credit and give working parents an extra bonus and have decided he thinks, in Tim Carney’s words, “Moms who stay at home with their children are less valuable than moms who work for pay.”

Some might say that this tax credit is piddling. Under Obama’s plan, parents would get an extra $3,000 a year to cover childcare, a service that costs more than three times that. But conservatives are miffed that families with one earner and one stay-at-home caretaker get penalized because they can’t get that credit.

What they don’t mention, however, is that families modeled after the 1950s vision of one working parent and one staying at home get plenty of tax preferences. The tax code has marriage penalties and bonuses for joint filers, and couples in which one spouse earns income and the other earns nothing “never incur a marriage penalty and almost always receive a marriage bonus,” according to the Tax Policy Center. This bonus is a remnant of policies that were put into place in the early twentieth century to keep women at home. We haven’t gotten rid of it even though more than 70 percent of mothers of young children are in the labor force. Couples where both spouses earn about the same figure, on the other hand, tend to see a penalty. Even if these couples get Obama’s new Second Earner Tax Credit of $500, it won’t come close to the $2,000-plus bonus that a middle-class married couple with unequal earnings got last year.

And as Josh Barro points out, single-earner households are getting a bonus another way: the labor a mother or father performs in the home caring for a kid or wiping down a counter is unpaid and therefore goes untaxed. When two parents work outside the home and pay someone to watch their children, both those incomes are taxed.

The conservative rush to defend stay-at-home mothers also usually only applies to a certain class of mothers. While the tax code has some benefits for families in which one parent stays home, the welfare system has huge penalties for any poor mother who might make the same choice. Welfare reform in the 1990s instituted stringent requirements that those who get assistance also work. The policy change was aimed at “welfare queens” who supposedly had more and more children to increase their benefits without wanting to work for money. Now, if a poor mother wants some cash assistance, she can’t make the choice to stay home.

And in some states, she also can’t make a choice about how many children to have. In most states, families get more money from the Temporary Assistance for Needy Families program if they have more children. This makes sense, given that it is costly to raise a child. Yet sixteen states have instituted caps on their welfare benefits, refusing to give poor mothers more money if they have more than a certain number of children. The caps were explicitly adopted to try to dissuade poor women from having more babies, although there’s little evidence that they work and people on public assistance have families that are the same size as those who aren’t.

There are policies that could help defray the sky-high cost of parenthood for all family types. One, as pointed out by Matt Bruenig, would be a simple, universal child benefit, paid out to all families for each kid they have as they do in the UK, Canada, and Nordic countries. But to say that giving two working parents a little more help constitutes a war on stay-at-home mothers ignores all the ways we already value—or don’t, depending on whether they’re poor—these women’s choices.