Pundits love generalizations. Half the world is this, the other half is that, and that explains just about everything.
Here, then, is our own generalization: the world consists of pagans and transcendentalists. Pagans eat, drink and sleep; transcendentalists work for world peace. Pagans believe that the way things are is the way things should be; transcendentalists believe that we were placed on this earth to change the way things are. Pagans worship nature; transcendentalists worship G‑d.
The Egyptians were pagans, the Hebrews were transcendentalists. The Hebrews were slaves to the Egyptians; then G‑d intervened, humiliated the Egyptians, freed the Hebrews and set them loose upon the world. This, in 30 words (more or less), is the story of the birth of the Jewish people.
Thus we read of ten plagues visited upon the Egyptians. These are usually understood as punishments for their cruel treatment of the Jews. But a closer reading of the Torah's account reveals that they also served a more basic function: to discredit the gods of Egypt so that "you shall know that I am G‑d."
The Nile -- Egypt's source of sustenance and most revered deity -- turns to blood; the soil turns to vermin, the skies rain a lethal deluge of fire and ice, the light of day turns to inky blackness. Nature is transformed from a nurturing mother into a capricious witch.
Taking the Jews out of Egypt would not have achieved anything if the Jews had taken Egypt along with them when they went. So first the Jews had to witness the destruction of Egypt's gods: they had to hear their masters renounce the natural order they had deified; they had to see the "goodness" of nature exposed for the sham that it is.
Only when the paganism of Egypt had been uprooted from their hearts, could the Children of Israel proceed to Mount Sinai to receive their mandate as "A light unto the nations." Only then could they teach the world that nature is not to be worshipped, but improved upon; that the way things are is to be supplanted with the way things ought to be.