Wikipedia ain't all that.

Columbia is a country that used to be both within South America and up the Isthmus to present-day Costa Rica. TR negotiated with Columbia to build a canal across the isthmus, picking-up where a French concessionaire had failed. The Columbians increased the demands beyond which TR was willing to pay. TR found a group of wealthy Columbian planters and businessmen with interests in the isthmus who supported the canal adventure on TR's terms. They started a revolution, which TR supported with gunboats and marines. After the "revolution" the new leaders negotiated a rent-to-own agreement with TR, if TR would build the canal.

Also, TR sent marines into Haiti and I believe Nicaragua. In both cases to 'protect American interests." This resulted in large fruit plantations owned by American companies whose boards were friends of TR's.

TR's many adventures in the name of the Monroe Doctrine were all successful during the time in which TR was president. His actions expanded phrase, "gunboat diplomacy" that we all think of as a Reagan invention. Reagan was a piker compared to TR.

here's an interesting link: http://www.mtholyoke.edu/acad/intrel/bush/boot.htm

Bot
edited to revise & extend comments.