But, ultimately, the problem isn’t just that Facebook doesn’t have the resources to pay for an army of well-paid, nuance-trained American editor-moderators (because, well: it does). It’s that doing so would undermine Facebook’s entire project. Facebook is built to engage its users, and to reward those users who produce engaging content. Every buzzkill debunking, every warning of caution, makes the site as a whole less engaging. This isn’t, really, Facebook’s fault, even: The bias toward news that confirms your beliefs — and the instinct to share that news — goes deep. All Facebook is doing is leveraging it. If it stops doing so, someone else will.