So very well put by Qcmbr
..... and all other 'believers' don't know that they are right they simply believe they are. Belief cannot be exposed and can rarely be reasoned with since belief by its very nature is our human response to a lack of evidence but it can be dislodged if it is constantly brought face to face with its cause and questioned therein.
Those outside the watchtower can see easily that it is built on nothing substantial beyond clan bonding, nothing remotely factual and is in fact - like all religions - a form of cage or social constraint - but for those within the cage looking outwards it is almost impossible to conceive that they are mentally trapped
and instead see the very bars that constrain them as in reality part of the cage that entraps those outside; as a caged animal at a zoo may percieve the human visitors as caged so the believer thinks they are free and unencumbered and all others just haven't realised yet.
To expose the cage one must merely hold up a large enough mirror. To expose the watchtower or any false system just hold up the mirror. My mirror was held up - inadvertantly -by a good friend who left my belief system and finally allowed myself to ask - and face the question - what are my beliefs actually based upon? Once I was brutally honest with myself I found my cage door wasn't even locked.