When it came to the foreign policies, the United States were not really pleasant towards the rest of the world. Besides the somewhat imperialistic policies that they had displayed, they fought others in terms of economy and migration. There were numerous laws introduced that prevented people form foreign countries from immigrating which wasn't liked by the other countries, while high tariffs made sure that exporting goods to the US was very difficult which was also problematic for various foreign countries.
"<span>It was practiced in Ancient Greece and Rome, yet became less common with the rise of Christianity" would be the best option from the list, since Christians tended to think that it was a sin. </span>
<span>It established the idea of "Separate, but equal.</span>
