During the 1840s, the United States gains more than a million square miles of new territory, the greatest wave of expansion since the Louisiana purchase. Much of the land is annexed in a struggle between the U..S. and its neighbor to the south-Mexic...
Great Britain amasses vast colonies in Asia and Africa in the second half of 19th century. With the exception of the United States, other countries scramble to join race. Many Americans loath the idea of imperialism and want the U. S. to remain focu...