What agency did the united states create to use cyber weapons and to defend against cyber attacks?

What event caused south carolina to secede from union in 1860

Which of the following most accurately describes china today

Which source would best a historian understand the effect of the great chicago fire on families? a. a biography of a chicago family displaced by the fire b. a letter from a grandmother in new york to her family in chicago c. a newspaper editorial about families who were displaced d. an oral history dictated by an adolescent who fled the fire