With great fanfare, your empire announces its intent to conquer one of humanity's most ancient dreams: sending a person to the moon. Launch day is still far away, but you have already received a cavalcade of questions from media outlets all over the world. When your astronauts reach the moon, whose flag will they fly? Will this be a victory for all humanity, or your empire alone?
Your empire's flag will fly proudly on the lunar surface, marking your achievement for all would-be opponents to see.
You promise to leave a banner commemorating the efforts of all your allied nations. This will be a monument for everyone.
You dodge the question; empty symbols of national pride do not interest you. For the right price, though...