The commander of the military operation on Friday at Amama Mbabazi’s home in Kampala described it as a mere change of guard.

But it is a fundamental change in the relations between the former prime minister and President Yoweri Museveni, his ally of four decades.

A convoy of military vehicles, sandwiched by police patrol pick-ups, turned up at Mbabazi’s home in Kololo, the upmarket suburb of the capital, on Thursday evening.

Planned and built by the colonial administration, these were once public houses occupied by senior civil servants. After the NRM leaders took power in 1986, they sold them to themselves at low prices. Today, the starting sale price of these houses is a million dollars.

The Kololo Airstrip, where most government ceremonies take place, is a stone’s throw away. Five times President Museveni has stood on a platform at the airstrip and been sworn into power. On each occasion, Mr Mbabazi was a key player.

However, Mr Mbabazi’s hopes of replacing President Museveni at the dais, of swapping his bridesmaid’s dress for the wedding gown, politically speaking, now face a stern test after he was fired as prime minister for refusing to back plans to endorse the incumbent as the sole NRM candidate in the 2016 elections.

But then, Mr Mbabazi is just the latest in a long line of allies who have fallen out with President Museveni when they stood in his way or threatened his grip on power. Some military rivals and adventurers often turned up dead, sometimes in mysterious circumstances.

A good example is Andrew Kayiira, a former guerilla leader and minister whose murder in 1987, a few weeks after his release from jail on treason charges, remains unresolved.

It is in the political arena, however, that the currency of loyalty has lost most of its value. From Betrayed by My Leader, penned by former fighter and MP John Kazoora, to Betrayed by former rebel co-ordinator, minister and MP Sam Njuba, and to a few more titles in between, there is a uniting narrative of being short-changed in the memoirs of those who have served with President Museveni.

Until Mr Mbabazi’s sacking last week, the biggest falling-out had been that with Eriya Kategaya in 2003 after President Museveni started machinations that would lead to the bribing of MPs to remove term limits from the Constitution so that he could seek re-election in 2006.

Seen by many as the de facto regime number two and described by some as President Museveni’s “childhood friend” despite the head of state publicly stating that he has no friends, Mr Kategaya was left out of a job and out of pocket when he opposed the leader.

He was further humiliated when he went back on his word and took a job in President Museveni’s government just to pay his bills, burying his reputation before his own death, from a blood clot, in Nairobi last year.

Which all makes Mr Mbabazi’s own fall from grace interesting and intriguing. He was, after all, the one who famously — or infamously, as it now turns out — accused Kizza Besigye of jumping the succession queue when the opposition politician declared his candidature against President Museveni in 2001.

A senior government official, who has served in the government for many years, says the falling-out “was an accident waiting to happen” as both men circled each other, waiting for the other to blink.

READ: Mbabazi had it coming, Museveni shocked him

“Mbabazi had to cement his place in the regime by working hard and appearing loyal during the day while finding time at night to be his own man and build his own power base, quite separate from Museveni at night,” said the official and friend of the two, who spoke on condition of anonymity.

“To build support openly would have seen him thrown out quickly, but to do so quietly would open him up to accusations of disloyalty when discovered, as appears to have happened.”

President Museveni, on the other hand, needed to show that the NRM was not a one-man party, and that it had other leaders who could replace him, without necessarily allowing them to do so.

There were many to choose from — including Crispus Kiyonga and Ruhakana Rugunda, the new prime minister — but Mr Mbabazi had the added attributes of a background in security and intelligence on top of being hardworking and ascetic.

Mr Mbabazi’s cause was aided by the waves of departures from the NRM. These included the youthful MPs and veterans such as Augustine Rugunda and Sam Njuba, who followed Dr Besigye in 2001; those dropped for opposing the third term “project”, such as Mr Kategaya, Amanya Mushega and Bidandi Ssali; those who fell foul of the rules, such as Maj-Gen Jim Muhwezi and Brig Henry Tumukunde; and those who died, such as Brig Noble Mayombo and James Wapakhabulo.

In addition, some “historicals” who stayed, such as Kahinda Otafiire, became pre-occupied with their sizeable business interests.

What fate did not drop in Mr Mbabazi’s hands he worked for quietly and cunningly, feeding off his experience as an intelligence agent and spy master. He made friends in the Israeli intelligence and security establishment and cultivated business contacts with Chinese firms and the civil service.

But it was in the NRM, where his wife and daughter also had deep tentacles, that Mr Mbabazi did most of his grassroots work, maintaining a close and steady relationship with party functionaries, even sending them Christmas cards and some cash in 2013, which rattled the intelligence agencies and pricked President Museveni’s antennae.

READ: Mbabazi’s wife calls Uganda’s NRM ‘fascist’

So much was the power that “Team Mbabazi” had accumulated in the party that the NRM primaries ahead of the 2011 elections were widely seen as a selection of vetted and preferred candidates rather than a free contest.

This accumulation of power did not go unnoticed and attempts to clip Mr Mbabazi’s wings have been going on for years.

State intelligence agents had a hand in fanning the flames of the Temangalo-NSSF land transaction investigation, including breaking into Mr Mbabazi’s daughter’s car, stealing a cheque leaf from it, forging a transaction and then leaking it to newsrooms.

Similarly, reports linking Mr Mbabazi to an investigation of transactions with foreign investors, since denied, turned up in the newspapers in a syndicated manner and, apparently, from the same source (a veteran journalist close to the anti-Mbabazi camp briefly came out of retirement and his pensioner job as a Pentecostal pastor, wrote one of the stories and promptly returned to retirement, just before a defamation lawsuit arrived in the mail).

By this time the power struggles had fragmented beyond the government-opposition divide to bruising internal fights along tribal, clan, ethnic and other lines.

A tender to build a hydropower dam at Karuma had to be called off when different factions of the first family ended up fronting different Chinese firms (President Museveni, who found himself increasingly sorting through policy briefs, security briefings and investor invoices, intervened by giving one faction the dam and the other another dam project).

READ: Museveni takes over Karuma power project, gets funding from China

Companies associated with Mr Mbabazi’s children suddenly discovered that they had been blacklisted from some of the tenders. When a massive fraud was discovered at the Office of the Prime Minister, Mr Mbabazi initially pointed a finger at the Permanent Secretary and accounting officer, Pius Bigirimana, but then went quiet after the President publicly defended the technocrat.

Relations between the two families, which have known each other for decades, suffered.

Although the then prime minister shared an office tower with First Lady Janet Museveni (in her capacity as Minister in charge of Karamoja), relations were frosty at best. The First Lady’s staff described the PM as “India”, using the code name intelligence agents had given Mr Mbabazi as they went about investigating him and his dealings. Mr Mbabazi’s own staff referred to the First Lady as “8th Floor” in apparent reference to where she sat.

As two camps coalesced around the two men, government officials found themselves having to take sides.

“It was clear that Mbabazi was likely going to be the next president,” a civil servant says, speaking on condition of anonymity in order not to fall foul of civil service rules, “so we had to work for him but also not appear to be disrespecting the President. It was tough.”

Civil servants in public media houses were not spared either.

At UBC, the public broadcaster, they took care to cover the president and include at least one item each from the First Lady and the Prime Minister. At the New Vision newspaper, where the government owns a controlling stake and the president appoints the CEO, editors carefully ensured that photos of the First Lady and the PM got prominent play in the early pages. The president often took the front page.

He can vie in 2021

By mobilising so extensively within the NRM, Mr Mbabazi hoped to stun the president by running against him for the party nomination, a job President Museveni has always been careful to receive without competition, according to pro-Museveni officials.

READ: How Museveni fell out with ally Mbabazi

Even if such a contest failed in 2016, they say, Mr Mbabazi has time on his hands. Now 65, he would be 72 at the next election in 2021 when President Museveni would be ineligible to contest on account of age.

Several officials interviewed, including many who favour President Museveni over Mr Mbabazi, highlight the need for a transition in a government that has been in power for nearly 30 years.

“It is long overdue to have some change. However good you are, time comes when you have to go,” a senior government official told The EastAfrican.

“What I’d very much like to hear is that at least those people —those whose job it is to make the decision — have agreed on a candidate to succeed Museveni.

“It is a big step but a step that must be taken.”

After promising, in 2001, that he was vying for his last term in office, President Museveni has gone on to contest twice and is now working on a third effort since then.

In each of those elections, President Museveni has given different reasons for wanting to stay on. In 2001 it was to modernise the army; in 2006 it was to promote regional integration; and in 2011 it was to improve service delivery and shepherd Uganda into an oil-producing country.

While no strategy has been unveiled for 2016 yet, in meetings with youth groups President Museveni has said he wants to hand over the baton to the younger generation, in effect locking out Mr Mbabazi and his contemporaries.

Most of Mr Mbabazi’s allies — and a few of his supporters — do not know whether to believe the president and his overtures to the youth or not.

Mr Rugunda, Mr Mbabazi’s replacement, is 66 and has been in Cabinet since 1986. More than 20 Cabinet ministers are above the official civil service retirement age of 60.

The president has tried, unsuccessfully, to reappoint former Chief Justice Benjamin Odoki, despite the judge having clocked the retirement age of 70 — and all in a country where more than seven out of every 10 people is below 30.

READ: One year later, Uganda awaits Chief Justice

President Museveni is loyal to his ageing friends and supporters but, as Mr Mbabazi has discovered, only if they do not harbour an ambition for his job. Yet, for every ally that falls by the wayside dozens queue up to fill the vacancy and pledge or renew allegiances.

Former vice-president Gilbert Bukenya, who once accused Mr Mbabazi of leading a “mafia” that fought him while in office, and who became a government critic after he was sacked, this week said he would be open to working with President Museveni again. It is the way of politics.

Following a recent reshuffle of district commissioners in which pro-Mbabazi officials were purged, survivors were quick to profess their loyalty to the status quo.

Some are eyeing the Ush90 billion given to State House for donations this financial year (by comparison, a university student loans scheme got Ush6 billion) — like the media executive who recently visited State House to profess his support for the re-election campaign and designate the editor-in-charge.

A major rally was in the offing for Saturday morning to welcome the president back from the UN General Assembly and thank him for appointing a new prime minister.

Mr Mbabazi’s allies admit they were a bit naïve in thinking they could outsmart, outlast and outflank President Museveni.

“There is a sense of betrayal,” one said on Thursday, just after clearing his desk. “This is like being married to someone for 40 years and then learning that the middle child is not yours.

“You wake up and realise that the things people have been telling you about your partner are true.”

If the sight of armed military police surrounding his home was a shocking sight for Mr Mbabazi, it is an ordinary one for Dr Besigye, whose house has had round-the-clock surveillance and a police cordon for years.

Col Dr Besigye was once President Museveni’s personal physician and blue-eyed boy. The president appointed him to Cabinet at 29 and made him the regime ideologue at 31. But when he dared President Museveni, Dr Besigye was forced into exile, jailed, assaulted and his supporters tortured or shot dead.

A week after trying to jump the queue, Mr Mbabazi’s house was surrounded by military police in an operation commanded by the chief of staff of the Land Forces, Brig Leopold Kyanda. An army general sat in a nearby hotel, co-ordinating the operation by telephone, as tents were unhitched, guns counted, radios dismantled.

There was no such drama for the other departing officials, however. In fact, the last time that happened, in the mid ’90s, it was Gen David Sejusa Tinyefuza’s guards who were being disarmed at his farm outside Kampala. So scared was the general that he soon made up with the regime, became its enforcer as co-ordinator of intelligence, before fleeing into exile last year.

Government spokesman Ofwono Opondo told The EastAfrican that Mr Mbabazi asked to be allowed to keep “at least one soldier and one gun”. The request was rejected. You can all belong to the NRM family but these bros ain’t loyal.

Some of Mr Mbabazi’s allies that this newspaper spoke to said they were preparing for “all eventualities” — including the possibility of charges being brought against him, as happened to Dr Besigye when he returned from exile in 2005 to challenge President Museveni for the top seat.

A source in the intelligence community said there was “renewed interest” in corruption allegations around the 2007 Commonwealth Heads of State and Government Summit in Kampala, as well as the shooting to death of an intruder at the Mbabazi residence in May 2009.

No formal investigation or arrests were made in the matter but the man’s body was exhumed and later reburied, with a police spokeswoman remarking: “Those specimens might be required in the future when the file comes up.”

The EastAfrican could not however find any pending charges against Mr Mbabazi or his close associates by press time.