Upon realizing they were under the threat of Dream Island and in a precarious situation, Japan, Canada, and Australia unanimously turned their gaze toward their big brother, The United States of America.
The reason these three countries were willing to form a United Fleet to trouble Dream Island was largely due to their own greed, but an even greater reason was the instigation and promises made by the U.S. Without the urging and promises of the U.S., they would definitely not have readily formed a United Fleet, nor would they have taken the initiative to offend Dream Island. So as soon as they found themselves embroiled in major trouble and their own safety threatened because of this matter, they immediately thought of seeking rescue from their powerful backer.