I think that debates of the kind you mention are meant to convince the audience. You won't get a fundamentalist to change his mind, but if you contract his b.s. with someone more sensible then the audience might leave with something to think about. Debates are a great way to challenge authority and generaly to show that the emperor has no clothes (show it to the people, not to him)

Re: persuasion... there's an element of persuasion in all we do. If we are asked to give reasons for everything we say and then reasons for that and so on, the chain of reasons must come to an end... it ends with unjustified/unjustifiable ideas/sentences. If I were to be asked if they are right, then I'd say that "yes", they are right, and if still pressed for answers I would say that I can't give reasons but that's want I learned, etc.
Wittgenstein made this point... that there are precise roles for the demanding and provoding justifications in our daily practices. This is one way in which philosophy goes bonkers, in expecting some pratices (such as asking for reasons) to always be meaningful, regardless of context.

To give Wittgenstein's example, if GE Moore would meet a prince who has been told that the world began with his birth, and who lived in a society in which that belief was central to their understanding of everything, Moore chould try to educate the prince on Mathematics, Physics, or even Kant's analysis of the categories of time and space, but in the end what the price must do is have a paradigm-change, in the Kuhnian sense, and let himself get persuaded by the world-view of Moore.

In other word, what you need to do is not only to put your ideas out there, but put them in a form that is attractive, so your lifestyle (in the grander, civilization-level sense) becomes more appealing than whatever beliefs your discussion partner has. Also, by simply acting our your thoughts and practices you are providing an example for your ideas.

If, for any reasons, anyone would want to know more, I'd recommand Wittgenstein's later work: Philosophical Investigations; On Certainty; Remarks on the Foundations of Mathematics

I like fundamentalists.

Anyway....!

Some debates have been very interesting. The famous debates between G. K. Chesterton and George Bernard Shaw were very good. Of course, I side with Chesterton and oppose Shaw down the line, but both were very good at setting out their positions. I have some tapes in which Leonard Peikoff and John Ridpath debated socialists, and a tape in which Peikoff debated Phyllis Schlafly (conservative) and Phil Wexler (liberal). I was very pleasantly surprised when I saw Wexler clapping and agreeing with Peikoff on foreign policy. He said he was an "anti-totalitarian" liberal. My kind of liberal.

But these debaters weren't like lawyers (sorry) just saying anything that would score points. They were saying what they honestly believed. As Chesterton once said, the man for whom any stick is good enough usually picks up a boomerang.

I don't engage in debates. I just express my views and dogmas. If somebody is persuaded by something I say, that's good, but it's not something I count on.

I certainly would not try to debate, e.g., a gun-grabber or a Holocaust denier or a 9/11-denier. Their value-premises are way too opposed to my own for there to be any meaningful communication.

As I've said before, fundamental value-premises cannot be reasoned to, only reasoned from.

Some people are extremely good at making their views attractive. The aforementioned G. K. Chesterton gives perhaps the most compelling case for Christianity in his Orthodoxy, The Everlasting Man, and other works. C. S. Lewis is also very good. I just finished reading a book on mythic themes and archetypes in Chesterton, Lewis, J. R. R. Tolkien, and Charles Williams. Now, I'm reading Taylor Caldwell's Dialogues with the Devil, a profound view of Christ, God and the Devil, Good and evil, Heaven and Hell. I find that Christian writers are usually the best writers, e.g., Milton, Dante, the Bible itself. And also a good preacher. I like the "fire-and-brimstone" style, and also preaching about the Blood of Christ. Christianity -- the historic Christianity of the West -- is extremely interesting.

Ayn Rand's novels The Fountainhead, Atlas Shrugged, and her earlier fiction dramatize the most powerful case for her egoist and capitalist ideals. I agree with the noble E. Merrill Root that Howard Roark is "far closer to theism -- and to the rainbow mind of Christ -- than anything dreamt of by the National Council of Churches." The style of that!

You can see that, while I cannot call myself a Christian, I am a Christophile.

In other words, a good myth is a powerful persuader for me. Myths are eternal archetypes. Myths are stories which tell us something of the character of the Divine. Myth is the language in which the Gods speak to us.

One very good book, Carl Cohen's Four Systems [Socialism, Individualism, Fascism, Communism], gives the best case for each of those four systems, the case as would be presented by its most eloquent spokesman. He even makes fascism and Communism look good.

I'm constantly debating within myself between my various characters. Wanda is very seductive. Dawn and Norma have superlative mythic style and also extremely captivating. Mr. Bricker has the most logical Constitutional argument. Around and around it goes, where it stops nobody knows....