Political debates are not about arguing with the other party. It's a show to influence the audience. Presidential debates are an obvious example. You don't be

Political debates are not about arguing with the other party. It's a show to influence the audience. Presidential debates are an obvious example. You don't believe your candidate thinks he can change the other's mind, do you. He thinks he can change the mind of someone in the audience. Or perhaps not even that, he just wants to boost morale by petting you, the passive follower of his, the right way. The same dynamic is in play in any twitter or online forum debate, including here. Well-written posts gets lots of upvotes, likes and "engagement" which illustrates my point nicely. It's not the other guy thinks, it's what the audience votes.