Common sentiment has it that of all of the ten trials undergone by Avraham Avinu, the Aqedah as the most difficult. After all, what could be more difficult than to acquiesce to God's command to offer up one's child, one's only child, who one loves, whose personality is so endearing and lovable as was that of Isaac. And, of course, generations of Jews have taken our Father Abraham's readiness to make ultimate sacrifices in the name of our ideals, for the Sanctification of God's Name in the World, as a model for imitation. (I discuss some of this here. The literature on the subject is just too massive to begin to cite. A simple Google produced over 100,000 hits and collections of further references.)
A teacher of mine in High School, though, once observed that Abraham's 'finest hour' is to be found in his defense of Sodom. Here he stood on very shakey ground, defending the right to live of the most depraved, self-indulgent, narcissistic and perverted societies since the Flood. Upon what did he base that defense, upon the possible existence of ten righteous men in Sodom?
What, though, were righteous people doing in Sodom? Why ten? Well, ten people would have constituted a significant presence, a community or 'edah' in Hebrew. Abraham evidently hoped that just as he had led thousands to repent, to abandon the depravities of idolatry and idolatrous self-worship, so such a minyan might be able to heal the spiritual rot that festered in the Sodomite body politic. If there were a minyan, Sodom might yet be saved. In the name of the possibility of Teshuvah, he was willing to stand up to God and bargain with Him.
In then end, Abraham won. God agreed to accept the possibility that a few good people can transform the most depraved, the most selfish and self-indulgent of cultures. The problem was, though, was that there was no minyan of Righteous men in Sodom. Either the former had given up on the cities of the plain, the latter had sunk so low as to be unsalvageable, or the former were unwilling to try (aside from Abraham) lest they be sucked in by the Sodomites.
Avraham Avinu, who apparently thought that his nephew could do the job, was willing to hold out hope for the cities of Sodom, Amorah, Adma, Tzvoyim and Tzoar. It was only when he saw that sometimes men just fig themselves a whole too deep that he accepted God's judgment and sadly, crushed, returned home. A Pyrrhic Victory indeed.