It¡¯s only natural to be skeptical when a political leader stands up and makes a promise about a target that¡¯s far off, hard to achieve, and lacks a clear pathway.

So one reaction to a report that Japan¡¯s new prime minister, Yoshihide Suga, will pledge next week to reduce the country¡¯s net carbon emissions to zero by 2050 might be: Really?

After all, public and private Japanese banks are still funding new coal-fired power stations in Vietnam, Indonesia and Bangladesh, exploiting a loophole in Tokyo¡¯s previous promise to reduce financing to such projects ¡ª a fact that¡¯s causing some consternation among European investment funds.