Tolkien's Characters

Alright, Im going way back to the Glorfindel and Arwen thing. (Hope nobody minds) I would say that Arwen wouldn't be able to stand up to the Ringwraiths the Glorfindel did. Yes, she may be a decendent from Luthien, but her father is Half-ELven. Therefore I'd say the power has waned through the generations. Glorfindel though had a power I don't think Arwen was meant to posess. I also say PJ unfolded Arwen's character in a completely diferent direction than what Tolkien had in mind. But who knows. Quesstion: Does it ever say that Arwen was a sheild-maiden? I can't remember ever reading that, even in the backround books.