The event of Ghadir was not only limited to appointment of a successor to the Holy Prophet (pbuh). Ghadir has two aspects: one is the appointment of a successor; the other is highlighting the issue of Imamate--what all Muslims gather from the word "Imamate." Imamate means leadership of the people and society in religious and worldly matters. This has been one of the essential issues throughout the long history of mankind. The issue of Imamate is not particular to Muslims or Shi'a Muslims. Imamate means that an individual or a group rules a society and determines the direction of their movement in worldly and spiritual matters: this is an issue for all human societies.
There can be two kinds of Imam. One is the kind that is described in the Holy Quran: "And We made them Imams, who guided (people) by Our command, and We revealed to them the act of doing good, keeping up with prayers, and the giving of the alms. Us (alone) did they serve." [The Holy Quran, 21: 73] This is the kind of Imam who guides people by God's order: the kind of Imam who protects people against dangers, pitfalls, and slips, leading them towards the desired goal of worldly life -- the life which has been bestowed upon humans, giving them an opportunity to reach that goal. That is one kind of Imam, and divine prophets are another example; the Holy Prophet (pbuh) is also an example of this kind of Imam.
Imam Baqir (a.s.) gathered people in Mina and said, "Surely the Messenger of God was the Imam." Divine prophets who were the most select of human beings are among this type of Imam. Their responsibility is to guide people; they are guided by Allah the Exalted; and, they transfer divine guidance to people. "And We revealed to them the act of doing good." Their actions are good deeds and "keeping up with prayers," --they keep up with daily prayers, which is the secret behind a strong relationship between man and God. "And Us (alone) did they serve," -- they are servants of God, just like all other humans who are servants of God. Their worldly dignity does not at all affect their heartfelt desire to serve God. This describes one type of Imam.
The other kind of Imam has been exemplified in the Holy Quran by the Pharaoh: "And We made them Imams who call to Fire." [The Holy Quran, 28: 41] (The Pharaoh was also this kind of Imam.) In this ayah, the word "Imam" has the same meaning as in the previous ayah I recited. That is to say, the worldly life of people, their religion, and their life in the hereafter are all controlled by the power of their chosen Imams, --who call people to the Fire-- Imams that can lead people to their destruction.
In spite of what they claim, even the most secular governments of the world are controlling the lives of the people, in this world and in the hereafter, whether they know it or not. The great cultural organizations that are leading younger generations, in all corners of the world, towards immorality and corruption are the same as those Imams who "call (people) to the Fire." Institutions of power call people to the Fire, because of their interests, because of their oppressive rule, and because of their desire to reach different political goals. The lives of people in this world and in the hereafter rests in their hands. They have full control over the bodies and souls of people.
A claim that the church of Christianity deals with spiritual matters, and the government deals with worldly matters is a fallacy. When power is in the hands of people, who are alienated from religion and ethics, the church will be at their service, spirituality will be crushed in the grasp of their powerful clutches, and the bodies and souls of humankind will be influenced by elements under their power: this is a persistent problem that humanity must deal with.
A society is either led by a just Imam --sent from God to guide people towards good deeds and justice-- or it's controlled by those (unjust leaders) who are alienated from justice and unfamiliar with it, bearing grudges against true justice in many cases: because, justice conflicts with their personal and material interests, so they hold grudges against it. It's always one of these two possibilities, and there is no third possibility.
Through the establishment of a government and a civil community in Medina, it was proven that Islam is not just limited to the offering of advice, preaching, and a verbal call to God: Islam wants the truths of divine rule to be realized in a society; and, this is not possible unless through the establishment of a divine government.
At the end of his life, the Holy Prophet (pbuh) selected his successor under the order and inspiration of God; of course, the history of Islam went off in a different direction, but this was what the Holy Prophet of Islam called for. And, this event became a model that went down in history. It is not right to think that the Holy Prophet's (pbuh) request (for a successor) failed. No, his request did not fail. It was simply that his request was not followed through with--in that era. However, his declaration was instilled in Muslim communities and journeyed throughout Islamic history; thus, today, you witness the results in this part of the Islamic world. By Allah's favor and His transforming power, this paradigm and this clear path will grow throughout the world of Islam on a daily basis. This is the underlining theme of Al-Ghadir.
Therefore, the issue of Ghadir is not a Shi'a issue. It is an issue for all Muslims; furthermore, for all humans. Thinkers are aware that this clear path is one that belongs to all humans: there is no other path. If evil people seize power in human communities, the world follow the direction of signs seem in the modern world. The more the world becomes modernized, the more dangerous those governments become. Of course, the more the world progresses in terms of knowledge, the more there is a possibility that a path of guidance will emerge. It is not the case that progression of knowledge pushes the path of guidance backwards. No, it progresses... along with the progression of knowledge.