The answer is. the construction of Panama canal
Big Stick Policy! He loved the saying 'speak softly and carry a big stick', meaning to use force instead of words when necessary. Formally, this was known as the Rosevelt Corollary, and it tied into the Monroe Doctrine.
The Southern Colonies, including Maryland, the Carolinas, Virginia, and Georgia were established during the 16th and 17th centuries. The Southern Colonies in North America were established by the British during the 16th and 17th centuries. At the time, they consisted of South Carolina, North Carolina, Maryland, Virginia, and Georgia; their historical names were the Colony and Dominion of Virginia, the Province of Carolina, and the Province of Georgia.
Florida (1819) In 1819, the United States signed the Adams-Onis Treaty with Spain, making Florida a part of the United States.
Missouri (1820) Missouri was added to the United States in 1820, as part of the famous Missouri Compromise.
Texas (1821) In 1821, a man named Stephen Austin led the first American families into Texas, which at the time, was still claimed by Spanish Mexico.
Hope This Helps! Have A Nice Day!!
