If we all come together then they can't divide one

from Nas (Ft. Damian Marley, Joss stone & Lil Wayne) – My Generation Lyrics on Rap Genius

What he means that some people (like colonizers-UK, US etc divide the men in colonies like they did in post independence India and Africa) on the basis of skin colour, religion. Example…brits created rift b/w Hindus and Muslims in India under their divide n rule policy….that gap lasts even today!
Lil wayne is saying that if we all come together—-unite then no one can divide us.
Yo, unity is strength

To help improve the meaning of these lyrics, visit "My Generation" by Nas (Ft. Damian Marley, Joss stone & Lil Wayne) Lyrics and leave a comment on the lyrics box