My friend said that as he never touched them he would need to capture them to be able to control. Is this true?
2 Answers
It does not appear so. Galadriel, who held Nenya, had this to say:
'He suspects, but he does not know - not yet. Do you not see now wherefore your coming is to us as the footstep of Doom? For if you fail, then we are laid bare to the Enemy.
(Lord of the Rings, Book 3, Chapter 7, "The Mirror of Galadriel")
Elrond says something similar at the Council:
all that has been wrought by those who wield the Three will turn to their undoing, and their minds and hearts will become revealed to Sauron, if he regains the One. It would be better if the Three had never been. That is his purpose.'
(Lord of the Rings, Book 2, Chapter 2, "The Council of Elrond")
These two Elves, who had held two of the three rings, seem to believe (no doubt with reason) that Sauron need not go near the elven-rings; presumably in much the same way that Celebrimbor had become aware of Sauron as he put the Ring on, so Sauron would be aware of the Elven-rings.
Galdor and Elrond seem to put the nail in the coffin at the Council of Elrond:
'What power still remains lies with us, here in Imladris, or with Cirdan at the Havens, or in Lorien. But have they the strength, have we here the strength to withstand the Enemy, the coming of Sauron at the last, when all else is overthrown?'
'I have not the strength,' said Elrond; 'neither have they.'
No, the Rings are linked, "he let a great part of his own former power into it, so that he could rule all the others" [The Shadow of the Past]. They shared a similar design and Sauron's work with the Elves in Eregion was all to this purpose of dominating the minds of others through the Rings. When Sauron first donned the One the Elves sensed him and took off their Rings and did not wear them again until the One was cut from his finger. If Sauron had ever regained the One he would be able to see what was done with the Three, who was wearing them, and to eventually dominate their wills. This was the purpose of the Rings, One to rule them all, so that he could control the free peoples. When Gandalf revealed to Frodo the nature of the One he said Sauron
will command them all again, wherever they be, even the Three, and all that has been wrought with them will be laid bare, and he will be stronger than ever. [The Shadow of the Past]
When one learns of the making of these magical objects it is said:
Now the Elves made many rings; but secretly Sauron made One Ring to rule all the others, and their power was bound up with it, to be subject wholly to it and to last only so long as it too should last. And much of the strength and will of Sauron passed into that One Ring; for the power of the Elven-rings was very great, and that which should govern them must be a thing of surpassing potency; and Sauron forged it in the Mountain of Fire in the Land of Shadow. And while he wore the One Ring he could perceive all the things that were done by means of the lesser rings, and he could see and govern the very thoughts of those that wore them. [Silmarillion; Of the Rings of Power and the Third Age]
At the first attempt to ensnare them Sauron failed since the Elves immediately became aware of him when he put on the One Ring. They
perceived that he would be master of them and of all that they wrought. [Of the Rings of Power and the Third Age]
This is why they never wore the Rings during the 2nd Age and they "concealed them and never again used them openly while Sauron kept the Ruling Ring." [Of the Rings of Power and the Third Age] They did wear them during the Third Age. Gil-galad gave his rings to Elrdon and Cirdan who eventually passed his Ring to Gandalf. Galadriel bore the other Ring.