It is true that, notwithstanding their alleged ignorance, they were wiser than their masters, and knew enough to be loyal, while
those
masters only knew enough to be rebels and traitors. It is true that
they fought side by side in the loyal cause with our gallant and
patriotic white soldiers, and that, but for their help,—divided
as the loyal States were,—the Rebels might have succeeded in
breaking up the Union, thereby entailing border wars and
troubles
of unknown duration and incalculable calamity. All this and more
is
true of these loyal negroes. Many daring exploits will be told to
their credit. Impartial history will paint them as men who
deserved
well of their country
Describe the effect Douglass achieves with his repetition of the words
loyal and rebel in this excerpt. What key concept is he trying to stress
with this repetition?