In 1902-03 Britain, Germany, and Italy blockaded Venezuela to force the payment of debts, and particularly when the Germans bombarded and destroyed a Venezuelan town; so agitated was American opinion that Roosevelt used a veiled threat to force Germany to accept arbitration of the debt question by the Hague Court. When the Dominican Republic defaulted on its foreign debt to several European countries in 1904, Roosevelt quickly established an American receivership of the Dominican customs in order to collect the revenues to meet the country's debt payments. Moreover, in his annual message to Congress of 1904, the president announced a new Latin-American policy, soon called the Roosevelt Corollary to the Monroe Doctrine--because the Monroe Doctrine forbade European use of force in the New World, the United States would itself take whatever action necessary to guarantee that Latin-American states gave no cause for such European intervention. It was, in fact, a considerable extension of the Monroe Doctrine, not a correct historical interpretation of it; but it remained the cornerstone of American policy in the Caribbean at least until 1928.
Encyclopedia Britannica, United States History: Imperialism, the Progressive era, and the rise to world power, 1896-1920