The people in the future on the show the 4400 have the power to alter humans why can't they save themselves?

Question

The future folks can also time travel as well as bestow gifts of clairvoyance, healing and mind control. So why do they need to alter the past to save the future?

Answer 1

It's a paradox, there sent from the future to save mankind be they are the cause of there own destruction. Just like Sargent Kyle Reese. (Terminator) If John Conner doesn't send him to save his mother in the past he would of never been conceived.