Let’s say I decide I’ve had enough with this whole Federation business and that humanity would be better represented by a Starfleet that follows my particular ideology. Assuming I could get enough people for crew and support, why can’t I start my own Starfleet?
I could replicate ship parts until I have a couple vessels. Go to new worlds and present myself as the official first contact of humanity. I could fly to Vulcan or Bajor and tell them no actually my organization represents humanity.
What’s going to stop me?
I suspect they couldn’t replicate dilithium because they’d be consuming dilithium, converting it to energy, then converting that energy back to dilithium.
The laws of thermodynamics state that this would be inefficient.