I agree with Whitey on this, he's said just about all I could say so I'll not bother adding to it, except for to say he should have waited until after the event to say it. To do it in the days leading up to it is obviously going to be seen as disrespectful.
The minute silence was indeed a mark of respect and it is a sad occasion indeed when people who were trying to enjoy their holidays end up being shot and killed. However, just because there is a minute silence does not make Russell Brand's comments irrelevant, wrong or misguided. It is clear that what he is saying is that the minute's silence per se is irrelevant in the big scheme of things. It will not alter government policy and it will not make the possibility of further attacks end. Russell Brand is merely stating that fact. The minute silence is indeed a smokescreen, it makes the government look compassionate, it looks good on the international stage, it panders to public opinion/perception about terror. To that extent it is a clever tool. Without a change in Government policy though there will be further deaths in some future scenario. Brand is not condemning 'minutes silences' as an idea. He is condemning Government policy and the propaganda that Government policy generates.
see Fired's earlier reply ( on another thread), what most people are saying is the attention seeking Brand could have kept his big flapping gob shut and made exactly the same point at a later less sensitive date.