Reuters: As UN climate talks enter their final days, the "Berlin Wall" that has for years divided rich and poor countries once again looms large as negotiators race to write a draft of a global deal that is meant to tear it down.
At the root of the problem is a 1992 U.N. climate Convention splits the world into rich and poor nations and obliges only the rich to cut emissions. Since then, however, nations such as Singapore or Mexico have grown rich but are still deemed "poor".
In Lima, representatives...