The correct answer is Isolationism.
Step-by-step explanation
Isolationism is an international policy doctrine that proposes governments should not intervene in external matters that do not pose a real threat to their country. In the case of the United States, during the presidency of President James Monroe (1917 - 1825) Isolationism was supported by him through the Monroe Doctrine that proposed European wars were issues that only affected Europeans, for this reason, the United States government should not intervene is these, similarly, Monroe opposed colonialism as this also imply countries intervening in matters that did not concern to them. So, the correct answer is Isolationism.