From the newsletter of 14th October 2021:
Left are greenhouse gas emissions in 2018, and right are cumulative greenhouse gas emissions, 1751-2018. Don’t think it’s China.
Prior COPs have been characterized by self-delusion so blatant that one of us (JEH) describes the backslapping congratulations at the end of the COPs as a fraud. We cannot blame it all on the political leaders, however. We scientists deserve a large part of the blame.
Scientists were slow to realize how low the targets must be for greenhouse gas (GHG) levels and for global warming to achieve a stable, healthy climate for young people and future generations. We also should have made clearer the effects of lags (delayed responses) in the climate system, as well as the time required to replace energy systems that are the largest source of GHGs.
Political leaders were slow to even set a meaningful goal. At last, with the Paris Agreement at COP21 in 2015, they set a goal to limit global warming to 1.5°C. Global warming had already reached about 1°C, so 1.5°C was believed to be the lowest feasible warming limit. However, the leaders did nothing to realize the two essential actions that the target implied (see below). Instead, they went home and took actions and allowed policies that made the goal unachievable.
James Hansen, Makiko Sato, 14th October 2021
Quoting again:
The most extraordinary fact revealed in Fig. 2 is probably current emissions by the U.K. The industrial revolution began in the U.K. and for a long period the U.K. had the highest emissions per capita. Yet U.K. per capita emissions today are about one-third of those in the United States, and U.K. emissions are declining rapidly.[4]
James Hansen, Makiko Sato, 14th October 2021
I also offer the following from the same post, although I say loudly I completely disagree with it:
Two actions are essential if we are to phase down GHG emissions rapidly. The first, as described many places, most recently at Can Young People Save Democracy and the Planet?,1 is the need for a rising carbon fee as a foundation that will make all other carbon-reduction policies work faster and more effectively. The funds (collected from fossil fuel companies) must be distributed uniformly to legal residents – otherwise the public will never allow the fee to rise to the levels needed to rapidly phase down carbon emissions.
The second essential action is whole-hearted support for development and deployment of modern nuclear power. Otherwise, gas will be the required complement to intermittent renewable energy for electricity generation. Gas implies pipelines, fracking, air and water pollution, and emission of CH4 and CO2 that would assure climate disaster. Modern nuclear power, in contrast, has the smallest environmental footprint of the potential energies because of its high energy density and the small volume of its waste, which is well-contained, unlike wastes of other energy sources.
Nuclear power is already the safest of all major energy sources,[13] based on deaths per kilowatt hour, but modern nuclear power is now far superior, with the ability to shut down in case of an anomaly and not require external power to keep the nuclear fuel cool. Nuclear power has also been the fastest way to deploy power to scale,12 which will be important for phasing out CO2 emissions in places such as China.
James Hansen, Makiko Sato, 14th October 2021
The only way nuclear is a viable alternative is if the peoples of, for instance, New England suburbs — and their environmentalist supporters — continue to insist that solar farms and wind turbine constellations cannot be located close to where they live. If they do that, then modular nuclear power, distributed and small scale, is the only way forward to mitigate climate disruption.
Choose your poison, New England.
Civ. 
ecoquant
