(Sep. 9, 2012) This is not an invitation to debate.
After some years of research into this, I am now writing this answer as to the "what and why" the NWO people are spraying, what's in their Chemtrails and why.
It is, bottom line, all about a vigorous form of planned population reduction from the current seven billions that now make up Earth's global human population to around five-hundred-million, world wide.
For perspective, The United States of America, in 2012, was reported to have a human population of 320 millions of persons.
This NWO plan has often been disclosed but covertly billed as "a necessary, rapid reduction of Earth's human population," to what a few have dubbed, "a sustainable human population for the planet."
But the planet wide population reduction isn't to be via starvation as many have suspected and posited. What is planned is lot more basic and insidious than starving the populations, will kill them a lot faster and will cause far more chaos and panic than almost anyone even suspects, allowing the global consolidations of government power, sought by the people who currently consider themselves to be and who seek to be the "elite" of the NWO.