AviK, you misunderstood me, or missed the next sentence- galus is not a blessing in itself, the fact that Hashem spread us out the way He did when he sent us into Galus was a “blessing” within the punishment, since it helped to preserve us, the galus just as easily could have been that we all were sent to Rome and stayed put there. The same way that Chazal say that the churban Beis Hamikdash had its benefits- because He took out his wrath on stone and wood instead of destroying Am Yisroel, which is what we really deserved. Obviously we rather neither happen, but Hashem “cushioned” the blow, so to speak in the manner that it was done.
Menu