I absolutely disagree that familial words - mother, father, sister and brother - are meaningless.
They invoke very clear attachments amongst humans as they are the words that define out social structure and our place inside the unit. They are extremely strong words and identifiers.
A cult or any organization or government can use the word as a way to manipulate an individual into replacing those feelings of identity, loyalty, committment, love, honor, respect etc as a move toward an allegiance in their membership that can either oppose or replace that of the familial entity.
That is why when you are a JW, your sister is not your one biological sister but many sisters - if you lose your biological sister, you have a warm family of many sisters. Ditto mother. Ditto brother - you respect the brothers - you may have no respect or attachment to your biological brothers.
The use of the word 'brother' invokes in most people, a feeling of brotherhood or family and unification. That is why the world is so important. Trust. You trust a brother - you might not trust 'sir'. Emotional connections are extremely important.
Fatherland? It is used to invoke a feeling of loyalty to the power that is your country. Ditto 'homeland'..a word not used much before Bush in order to invoke a 'them vs us' mentality. Emotion required to change laws and engage in security that you might not otherwise feel as attached to so quickly as when 'the homeland'...home is a word that pulls people in to a warm, fuzzy, protected and safe place you want to be at the end of the day.
All these words are extremely powerful and that is exactly what others realize when they make a choice to use them to recruit and maintain their membership and how they can more easily switch off that emotional and mental connection you may have to 'real' family and move closer to theirs. sammieswife