Over four centuries of human history are chronicled in this parsha, in which two sinful generations and their punishments are prominent. How do these two generations compare with each other?

Both generations are identified with monumental construction projects. Noach and his family are rescued from the Flood in the Ark:
And G-d said to Noach, “The end of all flesh has come before Me, for the earth is filled with violence through them; and behold I am about to destroy them from the earth. Make for yourself an Ark of gopher wood; make the Ark with compartments, and cover it inside and out with pitch”
(Bereishit 6:13-14).

Five generations later, mankind unites to build the Tower of Bavel:
And the whole world was of one language and of common purpose. And it was, when they traveled from the East that they discovered a valley in the land of Shin’ar and settled there. And they said to one another, “Come, let us make bricks and burn them in fire.” And the brick served them as stone, and the bitumen served them as mortar. And they said, “Come, let us build us a city, and a Tower with its top in the heavens, and let us make a name for ourselves, lest we be dispersed across the face of the whole earth” (11:1-4).

Those destroyed by the Flood are guilty of violence, while the project to build the city and Tower is an attempt to subvert Hashem’s will that all the earth be inhabited after the Flood (see 9:1,7,18-19; 10:5,20,31-32). The former abuse one another; the latter rebel against Hashem. Which is worse?

Our Sages consider this question in the Midrash (Bereishit Rabbah 38:6):
Said R. Eliezer: Who is worse, the one who says to the king, “Either you are in the palace, or I am,” or the one who says, “I am in the palace, and you are not”? Certainly, the one who says, “I am in the palace, and you are not”! This is what the generation of the Flood said, Who is the Almighty that we should serve Him? And what will we gain if we implore Him? (Iyov 21:15). The generation of the dispersion said, “It is not fair that He should choose the upper worlds for Himself and give us the lower worlds. So, come let us make ourselves a Tower and place an idol at the top with a sword in its hand appearing to go to war against Him.”

The generation of the Flood say, “Let G-d remain in His palace, and we will manage our lives without Him.” Theirs is a dog-eat-dog society, bent on anarchy. They want Hashem to remain uninvolved in the human sphere. Noach, in contrast, exemplifies Hashem’s true message to humanity, that He is intimately engaged in human affairs:
Noach walked with G-d (6:9).

For the builders of the Tower, Man is the supreme value, and the individual is subordinated to the collective. The results are dehumanization and tyranny. Avram, who at the time of the Tower is 48 and has recognized the Creator (Seder Olam), proclaims Hashem as the Source of all values Who holds each human being morally accountable.

The fate of the generation of the Flood is of their own doing; when Hashem destroys them with water, they effectively return to the world’s original state:
The earth was chaos, with darkness on the face of the deep, and the spirit of G-d hovering over the surface of the waters (1:2).
On the other hand, the consolidated Tower builders are punished with dissolution.

Each generation has modern parallels. The counterpart to the Flood generation is the “cult of science”:
… the popular philosophy of scientism … expresses itself on the conscious level in an attitude that regards all problems of life to be, at bottom, merely technical problems capable of solution simply by the application of “scientific method.” … ends and values lie in a realm beyond positive science …
(Will Herberg, Judaism and Modern Man).
Corresponding to the Tower builders are Marxism and Secular Humanism:
The highest being for man is man himself (Karl Marx).

Knowledge and power come from people and from the nature in which they live. … We rely on such sources as reason, observation, experimentation, creativity and artistic expression to address questions about the world and in seeking to understand our experiences (Society for Humanistic Judaism).

The generation of the Flood ignore G-d; the builders of the Tower of Bavel seek to usurp G-d. Accordingly, it would seem that the former were more sinful than the latter. Nevertheless, the former were completely destroyed, while the latter were merely thwarted, as the Midrash continues:
No remnant was left of the generation of the Flood, whereas the generation of the dispersion left a remnant!

The Midrash explains:
However, because the generation of the Flood were immersed in robbery, as it says, They remove landmarks, they steal the flock, and they feed (Iyov 24:2), therefore there is no remnant left of them. But the latter, since they loved one another, as it says, And the whole world was of one language, therefore a remnant is left of them.

Although undermining Hashem’s design, their unity and rapport, albeit misplaced, render them impervious to destruction, because, as the Midrash concludes,
Great is peace. … Says the Omnipresent, “I am not, as it were, able to control them, since there is peace amongst them.”

Noach lives in a world that banishes Hashem’s Presence, and although he walked with G-d, he has no effect on his generation. He is delivered from their doom in an Ark that, like him, floats above the chaos (R. Moshe Alshich, 1508-1600). 340 years after the Flood, humankind joins together to build a Tower to depose Hashem.

But, besides the Ark and the Tower, there is a third model of building — Avraham’s Tent of hospitality. There, each guest learns about his true place in society and his proper relationship to the Creator.