(I was asked to prepare a prayer for Peace in the Middle East in English, also using Hebrew or Yiddish, for an interfaith and inter-ethnic Peace program to be held on the Lower East Side in New York City, in June, 2013. Prayers for peace elsewhere in the world, in other languages, were given by other participants.
I was asked to create the prayer in a “petitionary,” rather than “affirmative” form. In “petitionary” form, we ask for something we don’t yet have. In “affirmative” form, we state that it is already ours. I use both, personally.
The siddur and machzor (Jewish prayerbooks) already contain prayers and hopes for ultimate world peace. I used these as models.
In the version here, I’ve also included a suggestion to visualize Peace as already achieved. Visualization is a deeper kind of “affirmative” prayer. We should visualize Peace before beginning the prayer, while we’re saying it, and after we’ve finished the words.)
G-d of us all,
In the Middle East, 
a place where so many peoples honor You,
Place peace, abundance, blessing, grace, love and mercy on us all.
Bless us all as one with the Light of Your Presence.
For in Your Light You give us
love and tenderness, justice, mercy and peace.
We bend the knee and bow before You, and ask as one:
G-d, please heal us. 
Heal us and we will be healed.
May it please You to bless all Your peoples with Peace.
Bless You, G-d, Who is making Peace in the Middle East.
 For “Middle East,” I turned to Rabbi Yehudah Ha-Levi’s poem, “My heart’s in the East” — לבי במזרח — in which he uses “mizrach” to indicate his beloved “East,” meaning the land of Israel, specifically Jerusalem. I used it generically to mean the entire Middle East, in order to pray for Peace not only between Israel and her neighbors, but for Peace within and between all the countries there, too.
 based on Mosheh’s prayer to heal Miriam (Bamidbar/Num. 12:13).
I changed the ending “lah” (her) to “lanu” (us) — i.e. heal us — which also keeps the poetic repetition of consonants in the Hebrew.
Heal us not only of outer expressions of war, but of things in us that cause war.