The policy debate on climate change has been largely restricted to a conversation between the left and center-left. (Don't get me started on conservatives, who have mostly decided to bury themselves in nutcase conspiracy theories.) The left essentially argues that capitalism needs deep, aggressive, and fundamental reform to be capable of tackling the civilization-threatening problem of climate change, while the center-left argues that markets can be made to kinda sorta hopefully work.

New York's Jonathan Chait put forward the center's case in a scathing review of Naomi Klein's book This Changes Everything last week, accusing her of gross analytical mistakes and a Tea Party-esque fixation on ideological purity. But for all his sneering, Chait does not land a clean hit on Klein, and does not address the large holes in his own Panglossian take on climate policy.

I reviewed Klein's book when it first came out a year ago. I concluded that while it was theoretically a bit muddled, her basic point that actually-existing capitalism was not yet dealing with climate change in a remotely serious way was right on.

This can be understood by a close examination of a recent New York cover story about climate policy by Chait himself. He piles up an impressive amount of evidence on new EPA regulations on coal power, incipient climate agreements with China, plummeting prices of solar panels, the upcoming climate talks in Paris, and so forth, arguing that humanity has turned the corner on climate change. "The good guys are starting to win," he writes.

All those things are true. But the more fundamental reality is that they are not enough to keep warming under the internationally-agreed target of 2 degrees Celsius. According to the IPCC, humanity can emit roughly 3.67 trillion total tons of carbon dioxide if we are to have a decent chance of staying under 2 degrees. As of 2011, we had already emitted 1.89 trillion tons, leaving 1.78 trillion remaining. At an emission rate of about 36 billion tons per year (and still increasing), humanity will lock in 2 degrees of warming by about 2045 absent heroic absolute reductions in emissions — and after that, things will start to get really bad.

Are current climate policies enough to get that down in time? Not even close. Detailed plans for keeping warming under 2 degrees involve reductions in developed country emissions — starting now — that haven't been seen outside of total economic collapse. I'm talking wartime mobilization levels of policy aggressiveness. In the real world, U.S. emissions are increasing. The developing world's have increased by a lot more.

All this reasoning (the "carbon budget" approach) is absent from Chait's piece. He has made exactly the same mistake as Clive Crook. Of course, the 2 degree guardrail is an arbitrary target (and as he correctly emphasizes climate success is a spectrum, not a simple failure/victory state), but fundamentally, one cannot judge the effectiveness of climate policy without a firm grasp of past, current, and future emissions.

At any rate, the de facto world plan of half-hearted government regulation plus "hope the price of renewables keeps plummeting" is sort of working, just not nearly fast enough. As David Roberts writes, absent some seriously huge political developments, "humanity is in for some awful sh-t."

That's why Klein, like other leftists searching for a positive spin on climate, are reduced to hoping that future disasters spur enough political mobilization to get the really aggressive policy necessary to save humanity from civilization-frying levels of warming. Either due to his shaky grasp of the basic facts, or because he loathes leftists in general and climate activists in particular, Chait spins this as Klein gleefully hoping for mass-casualty climate disasters so she can implement her bad Marxist agenda. It's an extraordinarily cheap shot that underlines nothing so much as Chait's own bad faith — and a double irony as it is activists like Klein and her "Blockadia" that provide the political impetus behind the recent policy successes Chait celebrates.

The extent to which the deep decarbonization plans the energy wonks are cooking up are "capitalist" is an interesting, if rather academic question. We can say that they imply massive interference with markets and property rights — the largest wholesale cancellation of private wealth since the abolition of slavery and the deliberate bankrupting of every existing carbon extraction company, just for starters. What's more, the signature market-based climate policy — the carbon tax — is theoretically shaky and has attracted little political support even outside the United States. But Chait and his cohorts on the center-left seem a lot less interested in drilling down into this question than in policing the left boundary of acceptable politics.