I was asking myself a question I'm sure has crossed everyone's minds : how can humans from the future slaughter and enslave their ancestors without jeopardizing their own existence ?
The question arose also in "Doctor Who" : in "The last of the time lords", the machines who killed 10% of mankind and enslaved the rest are revealed to be humans from the deep future. They can kill their ancestors because the Master has hijacked the Tardis and turned it into a "paradox machine" - making a time paradox sustainable for the space-time continuum. We can't expect such an explanation for Fringe, so what ?
We know the Baldies can move between dimensions and timelines. So the obvious answer would be : they are from A future, but not from the blue/amber universe future. The people they killed were not their direct ancestors.
So where are they from ? Maybe their home reality is the Red universe.So what if ... the only way to get rid of them is ... to destroy or radically alter the Red universe, to make sure the Observers never come to existence ? We've already seen the team using ZFT's methods ( and toxin ), but would they go that far ?