Whitman & Nietzsche: Drawing Comparisons

Few would expect these two writers to even be on opposite sides of a line on the same drawing board. Walt Whitman, as Prof. Robert Hass described, is the "grandfather of American poetry" and is known for his humanism, optimism, and general panache. In contrast, as we all probably know, Nietzsche is the "Continental Immoralist" and nihilist. Yet, consider the following lines:

There was never any more inception than there is now,
Nor any more youth or age than there is now;
And will never be any more perfection than there is now,
Nor any more heaven or hell than there is now

Urge and urge and urge,
Always the procreant urge of the world.
- Song of Myself

Although I do not have time to reference the specific lines from Nietzsche that can compare to this passage, it does strike me as containing similar themes. For one, there is the presumption of an eternal, static world, that cannot be qualified objective values or beliefs (time, aesthetics, morality). There is a sense of liberation in Whitman's work, just as Nietzsche "unfetters" himself from the belief in God, and the world is spinning "unchained to the Sun." Perhaps there are factors behind Nietzsche and Whitman that brought about this same belief of suspension and release from any grounding force, such as God.

What do you all think? Have we scratched the surface of some movement within Modernism that binds such appearingly different authors? I would love to hear what you all think...