One in Tokyo died. One in southern Britain died. And by this time the first one had started up so it could be killed again. And so it went on. Replication does not equal reliability.
Replication is good for reliability if things die for casual reasons.
If they die for certain, predictable reasons, replication has contributed nothing to you. We still don't really know what to do about that. Even if you could do that, Vinton Cerf would quite properly detonate at the idea of having such a Galactic Central, and we know even less about how to do such a thing on the basis of limited local knowledge - everyone looking around and coming to some sort of conclusion that something strange is happening. When one's talking about huge nets and uncertainty, one needs to engage in probabilistic modeling. And very remarkably over the last two or three years, it's turned out that some of the methods developed for statistical physics purposes can be applied to this sort of thing.