How did the united states change in the twentieth century? it welcomed european influence in the western hemisphere. it centered its energies upon improvement at home. it stayed out of foreign affairs. it was transformed into a respected world leader.

The answer is  It was transformed into a respected world leader. In the early many years of the twentieth century, the American individuals profited from mechanical development while likewise encountering its unfriendly impacts. Modest work and sequential construction system fabricating made large scale manufacturing conceivable. Railroad systems conveyed the mass-created products, a considerable lot of them the aftereffect of new advances, around the nation.