Short answers, pulled from the story.
President James Monroe delivered the speech on the 2nd of December 1823 during his seventh annual State of the Union Address. The doctrine declared that the New World was no longer subject to colonization by European countries.
John Quincy Adams, then secretary of state, wrote the main content of the policy while President James Monroe spoke before Congress. Alexander Hamilton had previously written about establishing the U.S. as a world power decades earlier but did not draft this specific document.
President Theodore Roosevelt asserted the right of the United States to intervene in Latin America for cases of flagrant and chronic wrongdoing by a nation. This shift aimed to preempt intervention by European creditors who demanded debt repayment from unstable governments.
President John F. Kennedy cited the Monroe Doctrine as grounds for confronting the Soviet Union over ballistic missiles installed on Cuban soil. The Cuban Revolution had established a communist government with ties to Moscow between 1953 and 1959.
Secretary of State John Kerry told the Organization of American States in November 2013 that the era of the Monroe Doctrine was over. He called for a mutual partnership with other countries in the Americas rather than unilateral dominance.