Nyerere alitaka Dr. Salim awe raisi wa Jamhuri ya Muungano wa Tanzania baada ya Mwalimu kung'atuka 1985. Lakini kulikuwa na upinzani mkubwa kutoka Baraza la Mapinduzi, Zanzibar, ambalo lina viongozi wenye ubaguzi. Walimpinga tena mwaka 2005 alipogombea uraisi wa Jamhuri ya Muungano.
Wapinzani wa Salim walisema pia kwamba akichaguliwa kuwa raisi, atalipiza kisasi kwa sababu Waarabu wengi waliuawa wakati wa mapinduzi. Kwahiyo, yeye kama Mwarabu, asipewe nafasi hiyo.
Halafu kuna ambao walisema alijua kuhusu mpango wa kumuua Karume kwa sababu aliwahi kuwa mwanachama wa Umma; pia kwa sababu alikuwa karibu sana na Abdulrahman Babu aliyelaumiwa, na kushitakiwa, kuwa kiongozi wa mpango wa kumuua Karume na kupindua serikali ya Zanzibar.
Pia kuna wapinzani wake ambao hawakupenda awe raisi wa Tanzania kwa sababu alikuwa karibu sana na Nyerere. Alikuwa mwaminifu kwa Nyerere na Nyerere pia alimpenda sana. Kwahiyo kumchagua Salim kuwa raisi ingekuwa ni sawa na kumchagua Nyerere kuendelea kuwa raisi wa Muungano pamoja na sera zake za ujamaa na kadhalika.
Pia Nyerere hakuambiwa ukweli na Wazanzibari fulani - mmoja wao Ali Hassan Mwinyi - waliosema watamuunga mkono Salim kuwa raisi wa Jamhuri ya Muungano.
Uamuzi wa viongozi hao wenye ubaguzi ulimzuia Dr. Salim kuwa raisi wa Tanzania - "one of the best presidents Tanzania never had."
Kuna mengi yaliyotokea kwenye mikutano ya viongozi wa visiwani na bara walipokutana Ikulu mwaka 1985 na kujadili nani awe raisi wa Muungano baada ya Nyerere kung'atuka. Mmoja wao ni Seif Sharif Hamad aliyekuwa kwenye mikutano hiyo kama mmoja wa viongozi kutoka Zanzibar. Ameandika yafwatayo katika kitabu, Race, Revolution, and The Struggle for Human Rights in Zanzibar: The Memoirs of Ali Sultan Issa and Seif Sharif Hamad:
"On April 12,1984, Prime Minister Sokoine, with whom we had excellent relations, died in a road accident....
Salim Ahmed Salim was appointed the new prime minister. He was forty-two years old, and I was forty-one; we were both from Pemba, both Front-liners, and both popular on the mainland.
Salim had actually once been a young member of the ZNP but had broken away when Babu formed the Umma Party. Karume had nominated him as Tanzania's ambassador to Egypt. Nyerere was very impressed by how seriously Salim took his responsibilities in Cairo; although very young, he was one of our best ambassadors....
He was very hard-working, clean, and incorruptible, and that impressed Mwalimu....The two of us had very good relations.
The hard-liners were obviously not happy with political developments in 1983 and 1984, so they began to intrigue. They knew Nyerere would soon retire from politics, so they plotted about who should succeed him. They did not want Salim Ahmed Salim - the new prime minister - and me to continue in our positions or to be considered for further promotion.
My sin was that I came from Pemba. They alleged, meanwhile, that Salim was an Arab, and as a former member of the Umma Party, he somehow knew of the conspiracy to kill Karume. They campaigned a lot and managed to convince some party elders that Salim should not be president because he would supposedly avenge the mistreatment of Arabs in Zanzibar during the revolution. History repeats itself because the same arguments were used against him in 2005.
Mwalimu thought Salim was the best candidate; Salim told me that Nyerere called him and said openly to him: 'I am leaving, and I think you're the proper person to succeed me.'
Salim told Nyerere that Vice President Mwinyi should automatically be the candidate for that position. Mwalimu replied, 'Don't worry about that because I've spoken to Ali, and he thinks you should take over.'
After that, Salim went to see Mwinyi, told him what Nyerere had said, and asked for his opinion. Mwinyi said Nyerere had consulted him, and he was not interested in the union presidency, adding, 'I'm satisfied in my present position as president of Zanzibar, and I think you're the proper person to lead Tanzania.'
Despite these conversations, the Liberators campaigned very hard for Mwinyi to succeed Nyerere, so we Front-Liners appointed a team to see Mwinyi. The team members emphasized that he was doing very well in Zanzibar, that Zanzibaris still needed him, and that it was inappropriate to abandon them when they placed so much hope in him. Mwinyi's response was, "Don't worry. Salim is the best candidate, and even if my name is proposed, I'll withdraw in favor of Salim.'
I also had a private talk with Mwinyi, and he reiterated that he was not interested in the union presidency. I advised Mwinyi that, if he really was not interested in succeeding Nyerere, he should personally tell him so. If he did not, it would be very difficult, as vice president, for his name not to be considered. He accepted my advice.
Yet when the time came in 1985 for the Central Committee to nominate candidates, we had dinner together in his private rooms, and he informed me that he had not gone to Nyerere as I had suggested. It was now clear that the man was interested.
The next morning the Central Committee met in the State House in Dar es Salaam to nominate candidates. Nyerere said that, first of all, the committee should spell out the qualities a candidate should possess, and about thirty-five qualities were mentioned.
After that, Nyerere said that we had three names to consider: Ali Hassan Mwinyi, Salim Ahmed Salim, and the secretary-general of the party, Rashidi Mfaume Kawawa.
Usually, those candidates who were mentioned then left while the others discussed their credentials. But before anyone left, Kawawa stood and asked the committee to withdraw his name, giving two reasons. First, he was not a very well man in terms of his health. Second, if he were nominated, people would generally think there would not be any changes, due to his long association with Nyerere since the 1950s. Nyerere said we had to respect Kawawa's views.
After that, Mwinyi and Salim were asked to leave. Really, the discussion was only about Mwinyi and whether the committee thought he had the necessary qualities. We agreed he had most of them, and Salim was not even discussed. Nyerere did not push Salim's name, probably because the Old Guard of both the TANU and the ASP teamed up to oppose him.
So the two candidates were called in and informed of the decision, and I could see the disappointment in Salim's face.
Salim was very loyal to Nyerere and did not expect this to happen. Salim never then or later ever uttered a word against Nyerere, but I blamed Nyerere, saying, 'Why did he give you all this hope? You had the right to be informed.'
He said, 'No, don't blame Mwalimu because he acted under pressure.'
He was very magnanimous, really." - (G. Thomas Burgess, ed., Race, Revolution, and The Struggle for Human Rights in Zanzibar: The Memoirs of Ali Sultan Issa and Seif Sharif Hamad, Athens, Ohio, USA: Ohio University Press, 2009, pp. 241, 245 - 246).