If we add up these three factors – the enormous economic challenge of reducing greenhouse gases, the complexity of climate science, and deliberate campaigns to confuse the public and discredit the science – we arrive at the fourth and over-arching problem: US politicians’ unwillingness or inability to formulate a sensible climate-change policy.
如果我们综合上述三个因素——减少温室气体排放的重大经济挑战、气候科学的复杂性、以及有意发起运动混淆视听败坏气候科学的名誉——我们就能得出第四个也是涉及面最广的问题： 美国政治家既不能也不愿制定切合实际的气候变化政策。