Are nations rational?

Rationality is something we ascribe to people, and ascribing it to something so amorphous as a nation state is reification (unless the behavior described is completely determined by a dictator). In democracies, policy comes out of a process of compromise among coalitions, each of which itself represents a compromise among individual members. Thus the Democrats and Republicans compromise on policy, while the Democratic and Republican positions are themselves compromises among the party factions. Moreover, decisions are made with respect to bundles of policies, with tradeoffs -- I will support your policy if you support mine. And of course, the government functionary implementing a policy is also implementing many other policies at the same time, to the best of his limited ability, if he/she is not actually going off on his/her own track. And of course, the citizens of a country -- as distinct from the guys "taking the kings shilling" -- do what they please, or what they think they can get away with.

I wonder, still, why so often in important things we see the majority view violated, even by governments that are designed and reputed to be the most democratic.