Why didn't the know nothing party survive beyond the 1950s?

The Know-Nothing Party believed that native-born citizens were superior to immigrants. They were anti-immigrants and wanted to restrict their abilities to become voting citizens. They didn't survive past the 1950s as ideals changed and they didn't have strong enough leaders to help the party draw more people.

answer; /// the correct answer is evidence of the olmec civilization has been found in southern american in a hot steamy forest, archaeologists have found earthen artifacts at several sites that were evidence of the olmec civilization. these   artifacts were mounds,courtyards and pyramids build of stones, also on top of the mounds were many monuments made of stone, some of these stone structures are very large, they weigh as much as 44

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