What is Ray Bradbury's tone about the rocket men?

Tone, of
course, is an author's attitude towards his or her subject.  I am intrigued by your question
because more than one of the stories within collection byconcerns the
"rocket men" you mention in your question.  In reality, though, that doesn't matter
because Ray Bradbury's tone toward any of "the rocket men" you ask about is always the
same:  it is a tone of both disillusionment and disagreement.

There are three
stories in question all of which contain the aforementioned "rocket men":  "The
Rocket," "The Rocket Man," and "Kaleidoscope."  In the former story, a
guy wastes his savings in order to simply pretend or "simulate" a real rocket trip
because he can't pay for a real one.  The author, Ray Bradbury, reveals his tone indirectly
through the happenings of the story.  In "The Rocket Man" a husband leaves his wife
and family time and time again in order to go back to the alluring "drug" of the
stars.  Humanity is left behind for the romantic ideal of starlit space.  Again, Bradbury shows
his own thoughts indirectly by showing that no good comes from this husband's space travel.  The
latter story, "Kaleidoscope," all of the "rocket men" here are thrown
tragically into space (to certain death) when their spaceship explodes.  Here, Bradbury reveals
his thoughts in the character of Hollis who realizes that the illusion of dreams can't
constitute a memory of reality.  One of the best quotes that sums up the tone is about the
mother in one of the stories who is steeped in reality (as opposed to the "dreams" of
the "rocket men"):

Mother wasn't afraid of the
sky in the day so much, but it was the night stars that she wanted to turn off, and sometimes I
could almost see her reaching for a switch in her mind, but never finding it.

In conclusion, it's important to note that no matter which story
you are referring to, Bradbury's tone remains the same:  one of disagreement or disillusionment
towards the "rocket men" and their space travel.  This leads to a further idea that
the simpler the life is, the better for the human race.