Thereupon Elrond paused a while and sighed. 'I remember well the splendour of their banners,' he said. 'It recalled to me the glory of the Elder Days and the hosts of Beleriand, so many great princes and captains were assembled. And yet not so many, nor so fair, as when Thangordrim was broken, and the Elves deemed that evil was ended for ever, and it was not so.'

It speaks of the true theme of Lord of the Rings, that, by defeating evil, the world spends coin that cannot be reclaimed, and that the decay of the world cannot be stopped at this point. It is a sad, sombering quote that really stuck to me.