It's like the Nazis and the Nations
Collaborating attempting to take over the Earth

from Eminem (Ft. Royce Da 5'9") – Bad Meets Evil Lyrics on Rap Genius

This means the Nazis and Nation of Islam—two forces on polar opposites of the spectrum joining together, and, well, attempting to take over the earth. Could be an obvious play on the fact that em is white and royce is black.

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