而当人们手中缺乏现成的模式来运作一个有效率的低碳经济时，共产主义阵营的政权更替就恰恰提供了这么一个人所共知的模式（至少在我们看来是这样的 ） 。
The regime change that took place in the communist world introduced a well-known model (or so we thought), whereas there is no existing model at hand for a low-carbon and yet efficient economy.