There are many paths to peace and self-mastery. The greatest challenge in all the paths is conflict - conflict with the world and others, which is ultimately a reflection of self-conflict. Self-conflict truly obstructs our paths to being better, more skillful, higher-achieving, more peaceful, and more serene beings.
In aikido we artificially simulate conflict situations on the practice mat. Initially, the "attacker" (called uke), grasps the practitioner's wrists or jacket in mildly threatening ways. Eventually the types of attacks can be more threatening and dynamic, but always performed in a safe way. By practising dealing with a variety of attacks using aikido, the practitioner develops relaxed self-confidence, not only on the mat, but also in daily life.
In aikido, while exploring how to deal with external conflict, i.e. simulated attacks, we are also learning to become aware of and explore our self-conflicts - our competitiveness, antagonism towards others, self-doubt, self-criticism, etc. As we realise and let go of these, our practice becomes more relaxed, our energy flows more strongly, and we experience a greater sense of harmony with our uke.
Ueshiba said that when we can eliminate self-conflict, we are then are in harmony with the world around us. Then there is no longer need for competition, no need for aggression, and no need for fear. What is left is peace and love, and the protection and care of our world.
The Art of Peace is the principle of non-resistance. Because it is non-resistant, it is victorious from the beginning. Those with evil intentions or contentious thoughts are instantly vanquished. The Art of Peace is invincible because it contends with nothing.- Morihei Ueshiba
P.S. Read an awesome presentation at the 2019 Summit LA by Aikido Journal editor Josh Gold, where he talks about how aikido transforms conflict into possibilities.