President Theodore Roosevelt used the Roosevelt Corollary in the Dominican Republic because he was afraid European countries would take action against the Dominican Republic if it did not pay its debts.
The Roosevelt Corollary was a substantial amendment to the Monroe Doctrine by President Theodore Roosevelt. In its altered state, the Monroe Doctrine would now consider Latin America and the Caribbean as territory to expand the commercial interests of the United States in the region, in addition to its original purpose of keeping European hegemony outside the hemisphere.
Roosevelt applied his variant to the Monroe Doctrine for the first time taking the customs of the Dominican Republic in 1905 to pay the foreign creditors of that nation. This event provoked a great indignation in the European leaders and in particular of the kaiser Wilhelm II.