[Diamond18]

I really have no trouble agreeing with Elrond's methods of going about things in the book. (I find him a bit different in the movie!) He doesn't forbid Arwen from ever marrying Aragorn. You have all discussed his reasons for putting the King stipulation on the match. All well and good. I have nothing to add on that.

Elrond realized something that Thingol did not, I think. In both cases, Arwen and Lúthien were already in love. Will a marriage vow alter their feelings? I don't think so. Point: their hearts were doomed to be broken anyway. Either they would be broken by the deaths of their husbands, or by being forbidden to marry them. It was really a lose lose situation.

So Thingol really couldn't do anything to save his daughter. What I'm getting around to it the old saying, "It is better to have loved and lost than never to have loved at all." Thingol and Elrond did not have control of their daughters' emotions...they could not tell them who or who not to love. They could only let them marry the men they loved and deal with the pain that would incur, or cause them pain by sundering them from the men they loved while the men still lived!

That is why Elrond let his daughter go. Thingol ended up letting his daughter go as well, but only after a lot of kicking and screaming. In the end, they both lost a daughter, but if you consider that even had Arwen and Lúthien stayed with them, they would have been broken versions of their former selves, and therefore would have caused their fathers sorrow.