What were the factors that lead to the u.s expanding abroad?

Black Lives Matter (BLM) is an international activist movement, originating in the African-American community that campaigns against violence toward African-Americans.  

The Civil Rights movement was a social movement which spanned and evolved from the mid 1950’s to late 1960’s. The movement’s goal was to end racial segregation and discrimination against African-American people along with securing federal citizenship rights.

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