Debating online is, most of the time, worthless, and you don’t need to be a genius to know that, and one of the biggest problems I see on online discussions is how everyone seems to be a master in the Art of Saying Nothing (also known as Autonomous System Number), here's the most basic way to do it:
Now, it's not every time that you are going to attack someone, sometimes you need to look like you're being constructive, so:
Say that the group, person or organization you're talking about REALLY needs to be more [Vague good adjective], be sure to not explain what you mean by that and to not suggest how to do that.
With enough training you can go to the intermediate level:
If you're a little bit lazy:
The most advanced level is really complicated and you need to study the levels before for a very long time to be able to do it, a great example is this article, which is shallow and useless, anyone can descontruct anything but to construct is what really matters. The jokes are bad and meta-humor is a clicle for years now.