What motivates an organization or a movement of any kind to persevere, even in the face of adversity? It is when the organization or movement is based on a concept or an idea of what it stands for or potentially can become. This holds true for very small organizations as well as the largest. It holds true for political, human rights, conservation, religious movements etc.
Ideas are powerful. They are more powerful than physical assets, more powerful than territory, more powerful than any one person. Having a powerful idea is a cornerstone that a successful organization or movement needs to be built upon.