Explain Roosevelt's "big stick" diplomacy?

Rosevelt wanted to project the strength of the United States by using a foreign policy called the big stick

See explanation.

Explanation:

President Roosevelt had a style of foreign policy that was to project strength by attitude and preparation without having to actually exercise action such as warfare. He was willing to take action, but hoped to avoid taking action.

To do this, he had the idea, and is quoted as saying "speak softly, and carry a big stick". This was where the notion of having a "big stick" comes from. Ideally, he thought that if he worked to make America strong enough and powerful enough to be obvious to aggressive nations, then they would not want to attack. To do this, he built up the military including the navy and including having a large army. He had the goal of never bluffing, but being willing and able to do what he and the nation decided must be done.