[Scott from the Left Coast]

I believe your understanding is correct -- and to pick a nit at myself, I shouldn't have said they were not man-made, but they were especially enchanted swords made by a very ancient race of men (which must obviously have had the power to perform such enchantment). They were magical swords, enchanted to be able to destroy their foes from Angmar with any successful blow. How even this ancient race achieved the ability to create magical weapons that could smite the Witch King, I don't know. Elrond was involved in this ancient war -- so perhaps there is Elven enchantment at work here after all.

[Bear_in_RoseBear]

perhaps there is Elven enchantment at work here after all.

This is true, after a fashion. The Numenoreans were descended from the Edain of the First Age, the original Elf-Friends. Their first king was Elros Tar-Minyatur, Elrond's brother (who chose to live as a Man). The Numenorean's deeper knowledge and wisdom originally came from the Elves, although they made their own discoveries as well, especially involving ship-building. At the height of their power in the Second Age, the Numenoreans were able to make Sauron himself a prisoner, without any help from the Elves.

Of course, Sauron got his revenge....