Other commenters have addressed how your claim that people behave more rationally when government is small. I would like to address the fact that even if we assume that citizens behave rationally, this does not mean that behavior maximizing personal benefit translates to behavior maximizing net benefit.
Consider, for example, the international politics arena, wherein there is no government over state actors, and where sufficiently important players pursue sufficiently rational actions, since the cost of not pursuing it is so high. Yet even with good evidence that current human activities are leading to future food and environmental insecurity via climate change, the rational actors have been struggling to coordinate on a plan.
Consider, for example, the international politics arena, wherein there is no government over state actors, and where sufficiently important players pursue sufficiently rational actions, since the cost of not pursuing it is so high. Yet even with good evidence that current human activities are leading to future food and environmental insecurity via climate change, the rational actors have been struggling to coordinate on a plan.