Why did the US start to think of itself as the World’s Protector of Peace?

"the plan of removing the aboriginal people who yet remain within the settled portions of the united states . . approaches its consummation. . an extensive region . . has been assigned for their permanent residence. it has been divided into districts and allotted among them. many have already removed and others are preparing to go. . " removal of southern indians to indian territory, 1835 this passage is most closely related to a) imperialism. b) the civil war. c) westward expansion. d) the french indian war.

Which of the following people did not run for president in 1848. a. lewis cass. b. zachary taylor. c. martin van buren. d. millard fillmore.

Can someone me out with this , i'm putting 30 points on it