Be constant in your practice, and one day the One who gave you the desire for the prayer of the heart will give you that prayer itself. When your heart's intention is fixed on God, it will keep lit the incense of your prayer, and wind of distraction will not put it out. do not worry about stray thoughts; they may come and go, but they will not take your attention away from God.
To the degree that each of us is dedicated to wanting there to be peace in the world, then we have to take responsibility when our own hearts and minds harden and close. We have to be brave enough to soften what is rigid, to find the soft spot and play with it. We have to have that kind of courage and take that kind of responsibility. That's the true practice of peace.