Yes, this sort of thing, but on a scale that is worth something. If you make it a worldwide thing, as this one was, you really need at least two, preferably three zeroes behind the number of attendees to suffice by now. If it was 300,000,000 Muslims marching against ISIS worldwide, I would be impressed by their efforts, and they would truly make a difference in a couple of days. 30,000,000 Muslims from worldwide would make a small but measurable dent that could be used for further work. 3,000,000 Muslims from the world over would be worthy of a mention, but too little to do much in itself. 300,000 Muslims from worldwide ... a passing note, at best.
30,000 Muslims from all over the world in UK is the best effort they show? Sick joke, nothing more. You can get more people to cheer a football game from a single city.
This might suffice (but not impress) 10 years ago and it would impress about 20 years ago, for example as a response to bombings of US embassies in Africa. Now we're talking about a whole lot larger effort to even make a slight dent in the problem. I did say the problem is increasing with time, didn't I? The larger the problem the larger the effort needed to fix it. If this were a weekly thing, on this scale, it might become worth something within a few years, but being done once? A drop in the ocean, nothing more.
No, not this kind of thing at all.
This is a Shia march against ISIS, who considers them heretics and attacks them first and foremost. They march against the people who would kill them and their families, there is no rejection of problematic teachings of Islam at all. Opposition to ISIS is welcome, but this doesn't do anything at all to solve the problems.
Note: I swapped your links by accident, your first link is my second and vice versa.
What else are they not doing I can link to for you?
Agreeing on which Hadiths are real and which ones are fake and need to be purged from record would be a good start ... but you probably can't link that. Agreeing on a common interpretation of the Koran and other holy texts would also be a rather urgent thing to do, but I also doubt you can link to that. Agreeing on a common arbiter in theological questions of the magnitude "
is peaceful coexistence with the unbelievers acceptable or not" would also be rather necessary, but you probably can't link that, either.
You know, the sort of thing other religions take for granted, but are entirely missing from Islam. Huge rallies against wackos are just something there is no excuse not to do. These other issues are immersed in difficulty. Urgent yes, necessary certainly, but also incredibly difficult to carry out. Vast rallies are downright trivial in comparison.
McHrozni