Alexandria Ocasio-Cortez has continued to show her power to steer the national political conversation. In an interview, Ocasio-Cortez suggested offhandedly that income above $10m may need to be taxed up to 70%, especially if we are going to get serious about halting climate change. Her idea instantly sparked indignant replies from the right. Grover Norquist compared it to slavery. National Review’s Brian Riedl called it “completely destructive”. Steve Scalise said she wanted to “take away 70% of your income and give it to leftist fantasy programs”.

Many critics attempt to confuse people over what Ocasio-Cortez said. Just to be clear: she said that when people earn $10m, the 10 millionth dollar and above should be taxed at a high rate. So unless you earn $10m, she’s not talking about “your” income. These are marginal tax rates, though the Republican party loves to trick people by conflating taxes that apply solely to the unfathomably rich with taxes that apply to ordinary workers.

In fact, Ocasio-Cortez didn’t even specifically say what she wanted the US tax rate to be: she said that “sometimes you see” a 70% tax on multi-multimillionaires. And that’s true: Sweden has a 70% top tax rate and consistently remains near the top of the Global Innovation Index. She pointed to the fact that across the world, in many successful social democratic countries, high earners pay more than they do in the United States. That’s a fact, and it should make people wary of talking points about how destructive any attempt to fund critical programs would be.

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Many of the arguments against taxes on the wealthy are “moralistic” rather than empirical. The argument that taxes on high earners are “slavery” is incoherent. Nobody forces you to earn $10m. When you are enslaved, someone makes you do work. Being wealthy is a choice – you could avoid the tax whenever you like by shedding your wealth and joining the working class. If we want to talk about “freedom”, the concentration of wealth at the very top has made the super-rich more free do as they please than anyone else, while it’s poor people who are faced with the choice to either work or suffer. If we want to talk about morality, having tremendous wealth when there is terrible deprivation cannot be justified.

The more intelligent criticism of Ocasio-Cortez is a pragmatic one. The National Review argument is that high tax rates simply can’t raise the kinds of revenue that would be necessary to fund a “Green New Deal”. This is, in part, because the rich would circumvent the tax through loopholes and moving money overseas. But this, in itself, is not an argument for not levying the tax: it’s an argument for closing loopholes and finding ways to effectively restrict the international movement of capital. If a law isn’t strong enough to achieve its proposed outcome, that’s an argument for improving the law.

It’s easy for the right to dismiss Ocasio-Cortez as a young and naive fantasist who “doesn’t understand economics” (though she does have a degree in it). But Nobel laureate Paul Krugman has confirmed that what she said is “fully in line with serious economic research”, citing the work of fellow Nobel laureate Peter Diamond, who put the optimal top tax rate even higher than Ocasio-Cortez. Once we put aside the “taxation is slavery” silliness, the question is: “What rates maximize revenues?” National Review’s Riedl argues that high taxes cannot fund the full Green New Deal plan. But even then the real question is: how much climate action can we fund?

That question is critical, because Ocasio-Cortez isn’t proposing federal spending for its own sake. The reason progressives are pushing a Green New Deal is because the entire planet is in mortal peril. “We can’t afford it” isn’t an option, because not dealing with this problem will impose costs on our children that are far higher than anything we might need to spend today.

Stopping climate change is an investment, and so the question has to be “How are we going to do it?” rather than “Do we have the money to do it?” The National Review is correct that the left has to move beyond talking points and “actually lay out a specific, comprehensive proposal of spending and tax increases”. But critics of left proposals, too, need to be explaining how they think we can achieve the urgent goals put forth by the Intergovernmental Panel on Climate Change.

Here’s the good news: even when conservatives are fuming about Ocasio-Cortez, they cannot stop talking about her ideas. The Green New Deal climate change plan has gone from marginal to mainstream almost overnight. Now, Fox is hosting entire panel discussions to debate her policies, and they often end up using their own information channel to make left ideas look appealing. They are frustrated in part because the more they denounce “socialist” ideas, they more popular the ideas become.

“Her time to be popular is over,” a Fox news panelist said wishfully of Alexandria Ocasio-Cortez. I very much doubt that it is.

