Answer: The effect of moral diplomacy on an American foreign country would be that it would become a democracy.
Step-by-step explanation: President Woodrow Wilson believed that as a democratic nation, it was the duty of the United States to help other countries become democratic in governance and allow the citizens of the respective countries to have a say in the government. For this belief of his, he used the military might of the US to bring democracy in countries where there were non-democratic authoritarian rules. He called this policy as 'moral diplomacy'.