Bad policy, including continuing the effective no-policy policy which is the easiest bad policy, is probably the likeliest outcome. But we very much need a good policy despite the odds.
Doing policy right is a huge challenge to global collective decision-making, which (GATT, WTO, IATA etc.) has some successes that people somehow like to forget.
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One idea going under the rubric of “lukewarmism” is that getting to zero is not important, so that the no-policy policy is fine. On this view, we just need to slow down a little. This simply fails to understand the physical constraints on the problem.
Another view, until recently called the "breakthrough" view and now being rebranded as "ecomodernism", also supports the no-policy policy while at least bowing in the direction of a carbon neutral future.
That new “ecomodernist” push implicitly restates the Breakthrough Institute (BTI) position that getting to zero follows from technological innovation alone. Again there is no need for a policy instrument on that view. That is exactly the stated position of the main players in the fossil fuel industry. But the immense economic interests of that industry are in slowing that transition down. If they extract the full book value of their reserves, which “fiduciary responsibility” says they are supposed to do, the outcome will likely be somewhere between grim and cataclysmic. Avoiding that is the reason we need a globally binding policy.
Bjorn Lomborg adopts both of these positions - he advocates that the problem, while real, is smallish AND that technology will solve it left to its own devices with perhaps some research subsidies but no regulatory effort.
“Lukewarmism” and “ecomodernism” are wishful thinking in my opinion.
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In the real world, there is a fossil fuel industry, and the imperatives of capitalism put them under enormous pressure to do us harm. Some sort of global regulatory instrument is needed. Doing this responsibly and effectively will be very difficult. The fact that lots of people would just as soon that such a process fail for their own ideological reasons just makes matters even harder.
On the whole, I agree with the ecomodernism perspective, that we ought recognize the immense capabilities of modern science and technology. Though I have some problems with his recent essay, on the whole I agree with Stewart Brand (who indeed has always been an inspiration to me) that we should work toward a world not just of defending a shrinking natural endowment but of enhancing it. See the Planet3.0 manifesto (which I wrote, drawing extensively on Bruce Sterling and David Schaller) for more. Is it ecomodernist? Maybe so.
But to the extent that the ecomodernist manifesto does not take account of the real-world obstacles to that goal, it ducks the very question it pretends to be addressing. There is no workaround to a global, binding treaty.
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UPDATE: Hmm, there's a problem with this stance. The Planet3.0 manifesto is pretty handwavy on how to jump those hurdles too (though it does at least allude to them).
More to follow.