It is difficult to make comparisons: every situation is different.
The earthquake in Abruzzo was strong but the geological composition of territory was very different compared to Emilia. Moreover, the amount of old buildings in Emilia was higher, so more damaged monuments there
Some time ago I read a Ken Follet’s novel, the hammer of Eden. There the author made a very interesting statement, but I have no idea if is a totally dumb fantasy or if there is something true.
The most violent earthquake are caused by the huge amount of energy accumulated by tectonic plate movements because friction doesn’t allow the free movement. So, when energy is high enough to overwhelm friction, there is a sudden sliding of plates, and this cause earthquakes.
In the novel, it is speculated that causing small and controlled explosions underground can cause slight movements of plates, avoiding the accumulation of a too high energy, and then causing small but controlled earthquakes that cause only small damaged.
To better give an idea of this principle, in the novel is reported an example. If you put a brick over an inclined plane, the friction prevents the brick to fall down, but if you slightly hit the inclined plane with a hammer, the friction is slightly reduced and the brick can slide down slowly and in controlled way.
As I said, I have no idea if it is only a fantasy, but the principle seems interesting. I wonder if is really possible to prevent big earthquakes in this way