We've been very impressed with Jonathan Cook's writing recently...
Externalities are not incidental to the way capitalist economies run. They are integral to them. After all, it is a legal obligation on private companies to maximise profits for their shareholders – in addition, of course, to the personal incentive bosses have to enrich themselves, and each company’s need to avoid making themselves vulnerable to more profitable and predatory competitors in the marketplace.
Companies are therefore motivated to offload as many costs as possible on to others. As we shall see, externalities mean someone other than the company itself pays the true cost behind its profits"