According to Imam Khomeini one of the main reasons of the Muslims separation is self-desires obeisance and personal purposes allegiance. Especially when Islamic countries governors, focus on their own illegitimate desires instead of emphasizing on Muslims benefits, Muslim Imams address them in this way:
"When do the Muslims and their governments want to wake up? When do they want to put aside their personal interests and enmities and serve their nation? Muslims are almost one billion." (1)
Imam also believed that if Muslims be aware of their abilities and be together no power will be able to stop them, like how Iranian people could fight against superpowers while there were a few:
"When do these governments want to wake up and give up their enmities? When do the Muslims want to come to know what is good for them and what is bad? When do they want to get rid of this pain?" (2)
Source: The Unity Architecture, Page: 21