I think that Doug misses the in your face to God issue that the rainbow presents.Ge 6:13 And God said unto Noah, The end of all flesh is come before me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth.
Ge 7:6 And Noah was six hundred years old when the flood of waters was upon the earth.
9:11 And I will establish my covenant with you; neither shall all flesh be cut off any more by the waters of a flood; neither shall there any more be a flood to destroy the earth.
9:12 And God said, This is the token of the covenant which I make between me and you and every living creature that is with you, for perpetual generations:
9:13 I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth.
9:14 And it shall come to pass, when I bring a cloud over the earth, that the bow shall be seen in the cloud:
9:15 And I will remember my covenant, which is between me and you and every living creature of all flesh; and the waters shall no more become a flood to destroy all flesh.
9:16 And the bow shall be in the cloud; and I will look upon it, that I may remember the everlasting covenant between God and every living creature of all flesh that is upon the earth.
9:17 And God said unto Noah, This is the token of the covenant, which I have established between me and all flesh that is upon the earth.
By waiving the rainbow they are saying to God they can do what every they please and that he promised that he won't flood the earth