Answer:
it educational groups i believe
Explanation:
Sectionalism affects the population of the United States based on the majority of American citizens only concerned with what goes on within the American borders, or what happens to citizens of the United States, whether they are here or abroad. Some believe we should not involve ourselves in matters that seemingly have nothing to do with the United States.
The biggest impact that started WW1 was the assassination of Archduke Franz Ferdinand.
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These are speculations, but not without some documentary evidence