It is critical that we come to understand that the right use of will is neither about bending the will of others to our own selfish agenda nor is it about surrendering one's will to divine will as if it were something foriegn; rather, will is the embodiment of one's life purpose in all that one does. Such embodiment is divine. In this way, there is no conflict between Heaven and Earth.
The Iron Mandala pertains to the right use of intent, volition, intuition, and will, represented by the Iron Horse. The proper use of will presents both strength and grace like a horse running freely across fields, living in accord with its nature, intent upon one thing at a time: when it runs, it runs; when it eats, it eats; when it stands watch, it watches. Also, like steel, there are times when one's will must be unyielding and times when it must be flexible. So, too, we must be intent upon our life's purpose.
The Will has been misunderstood, punished, denied, and otherwise abused for so long that most people no longer know what it is. It is neither positive thinking nor "getting one's way"; rather, it is the unification of intuition, intent, and volition arising from the entirety of one's being--body, will, heart, mind, and spirit--to live one's truth.
This understanding enables one to heal the historic and soul-denying rupture between Spirit and Will. By restoring unity, we find that healing occurs naturally and the myriad facets of our lives are brought into harmony in the Heart, giving rise to compassion, grace, and wisdom. This is the Way of the Dragon.
I recommend checking out the Right Use of Will website for more information on the subject and reading the Right Use of Will book series by Ceanne DeRohan. Also, a great book about the use of will is Roberto Assagioli's insightful work, The Act of Will.
"Only the development of his inner powers can offset the dangers inherent in man's losing control of the tremendous natural forces at his disposal and becoming the victim of his own achievements." - Roberto Assagioli, The Act of Will, 2002, p. 6