This is a might strange but here goes. The Tower of Babel had one language at that time and was trying to get eternal life not contact God. Those people were not dumb and the tower was a means to try and obtain eternal life through science. Could normal man get eternal life, well remember that God had to put a angel between man and the Tree of Life. To stop carnal man from intering a area not allowed. So it was with the tower folks, they did not live so long from Noah's time and remember that possible that God used the Science of that time to creat a atom bomb to destroy the sinful world.