universal peace; peaceful world
A yojijukugo describing a state where the whole country or world is at peace and nothing eventful happens. Literary and somewhat rare; used in formal or poetic contexts.
I wish for a world of universal peace.
天下泰平 also means 'peaceful world', but is more common and less literary. 千里同風 emphasizes the idea of peace extending everywhere without incident.
A classical Chinese expression literally meaning “the same wind for a thousand leagues.” 同風 refers to shared customs or a realm unified under the same civilizing influence, hence universal order or peace.