What bring about the feelings of sectionism in us

Why did president lincoln place general mclellan under the command of general halleck? a. mcclellan failed to capture richmond. b. mcclellan was responsible for the north's defeat at the second battle of bull run. c. mcclellan failed to defeat lee at antietam creek.

America withdrew from vietnam because of military failure

How has germany developed through the 19th centuryexplain in about 100 words the sequence of events that led to the nation’s unification.btw if u use any sources (aka websites) lemme kno