i need help in english plz?

Question

hi, can you summarize the passage? what is the theme? sorry I can't understande english that well.
"Americans have made themselves notorious by the shrillness and the brutality with which they have insisted on this idea, but they did not invent it; and it has escaped the world's notice that those very excesses of which Americans have been guilty imply a certain, unprecedented uneasiness over the idea's life and power, if not, indeed, the idea's validity. The idea of white supremacy rests simply on the fact that white men are the creators of civilization and are therefore civilization's guardians and defenders. Thus it was impossible for Americans to accept the blakc man as one of themselves, for to do so was to jeopardize their status as white men. But not so to accept him was to deny his human reality, his human weight and complexity, and the strain of denying the overwhelmingly undeniable force Americans into rationalizations so fantastic that they approached the pathological.

Answer 1

The passage deals with the phychology of white supremacy. It developed because white people believed that they developed civilization, and would be its guardian and defender. The US, while not the inventor of this, became its best-known proponent. This was buttressed by the abolition of slavery and the attitude, particularly in the south, that the black man required time to learn civilization, and until then could be held in a status approximating slavery, which would slow the process and justify it since the blacks made such slow progress. The architecture of segregation that was set up was fantastic as to its rules, and the actions that went into enforcing them would have been ridiculous if they weren't so tragic. In fact they were an example of "white terror" that we foisted on our own people that caused more damage than did 9/11.

(I added some material that I feel explained the American attitude more than did the passage)