The peace and prosperity means surrender to Kṛṣṇa. Then you become out of the clutches of māyā. That secret they do not know.
Lecture on SB 1.5.11 -- New Vrindaban, June 10, 1969:
So all of them are searching about the... Devotees, they have finished their searching. They have found out the real truth. Īśvaraḥ paramaḥ kṛṣṇaḥ (Bs. 5.1), the Supreme. So it is a question of degrees of spiritual understanding. So there are three million serious sādhus in India. None of them ever attended such Mahatma Gandhi's meeting, neither they invited Mahatma Gandhi. No. They never never recognized, recognized. Because what they have got to do with these political affairs? Just like... They know, this is the business of the crows. The crows will take interest in such meeting. Punaḥ punaś carvita-carvaṇānām (SB 7.5.30). What these politicians will do? They'll simply make plan. That's all. Hitler will make one plan, Mussolini will make one plan, Churchill will make another plan. Your Roosevelt will make another plan, Gandhi will make another. Simply planmaking business. They will never be able to bring any peace and prosperity in the world. That is not possible. Because it is under the grip of māyā. They do not know. The peace and prosperity means surrender to Kṛṣṇa. Then you become out of the clutches of māyā. That secret they do not know. They're simply making plans. That's all. So planmaking, will always be frustrated. So simply agitation; it has no meaning. Therefore those who are transcendentalists, they know, this is crow's meeting. Sometimes, you have not seen, crows meeting. Kaw kaw kaw kaw kaw kaw kaw. They are passing resolution. You see? (laughter) You have seen crow's meeting?
taken from: https://vaniquotes.org/wiki/Peace_and_prosperity_means