Zimbabwe’s President Robert Mugabe is heading  – unsteadily on his 92-year-old legs – towards a meeting this week that threatens to be either his undoing, or that of the country’s tottering economy.

In the City Sports Stadium next to Harare’s business centre he is due to hold talks with some 10,000 members of the Zimbabwe National Liberation War Veterans Association (ZNLWVA), a barbarous militia which he has used to keep him out of trouble since 2000 when he was seriously challenged for the first time by a national wave of sentiment for democracy.

The last time Mugabe was confronted by the “warvets,” ex-guerillas from the uprising against the white-run Rhodesian government, was in August 1997 when they wanted a staggeringly large increase in their monthly pension payments. Led by Chenjerai “Hitler” Hunzvi, a Polish-trained medical doctor with a dubious war background and a talent for extortion and brutality, about 40 of them confronted him in a secret meeting at his official residence in Harare and told him they would effectively have him deposed if he refused.

The meeting was one of the most significant events in the country’s post-independence history, but the local media regarded it as too sensitive to report, and the foreign correspondents who picked it up couldn’t believe it. Mugabe had caved in to the veterans, and ordered his finance minister to give each one of their 40,000-odd members a one-off payment of Zimbabwean dollars 50,000 (then about US$6,250) costing some Zimbabwe dollars 2 billion, and a permanent monthly stipend of Zimbabwe $2,000.

With a jolt it set off the beginning of the Zimbabwe economy’s descent to hyperinflation and ruin. “Who ever heard of a country going bankrupt?” he asked. Three months later, on November 14, the Zimbabwe dollar plunged 72 percent, and the day is remembered as “Black Friday” and it set off the crash of virtually every other economic indicator.

Mugabe didn’t give a hoot. He had bought the war veterans loyalty and from then on used them as a rabble of thug mercenaries.

Their first assignment came on December 11 that year when about 5,000 pro-democracy supporters marched peacefully in the streets of Harare, calling for political change. They were met by a column of warvets, who set about them with bricks, barbed wire, clubs, whips, and tyre levers. Miraculously no-one was killed but the effect of the brutal assault was to ensure that that there hasn’t been another large demonstration against Mugabe.

They were used as the primary enforcers in Mugabe’s land grab that started the next year, brutalising white farmers, their families and their workers, and at the same time against opposition leader Morgan Tsvangirai’s MDC party, in a reign of murder, rape, torture and destruction.

Ahead of every election now, war veterans are deployed across the country’s rural areas to terrorise villagers into voting for Mugabe’s ZANU(PF) party. In the public “outreach” period to gauge what ordinary people wanted in a new constitution in 2013, the veterans ensured that villager after villager declared without variation that they wanted Mugabe as president and to have as many terms as he wanted.

The veterans like to characterise themselves with words like “valiant,” “courageous,” “gallant” and ”heroic.” The fact is that they carry out their missions in the knowledge that they are guaranteed complete immunity from any official interference.

In the beginning authorities took a little while to afford them immunity. In 2000 local television showed a group of warvets who had seized a farm north of the western city of Bulawayo. The owner called the police who arrived and marched on the invaders. The veterans fled in mayhem.

In February this year the veterans’ chairman, Chris Mutsvangwa, called a meeting where they expected they would meet Mugabe and spell out to him their dislike of his wife and her political ambitions. Several hundred of them were met on their way by riot police with tear-gas and water cannon. They scattered in disarray. A handful of minor injuries were reported. “We equate such brutality to the South African Marikana scenario,” said Mutsvangwa.

Judith Todd, the daughter of the late liberal former prime minister of Rhodesia, devoted herself from independence in 1980 to the welfare of war veterans. In 1981 the government formed a demobilisation directorate, she pointed out in a letter published widely here in 1997. A total of 41,000 were demobilised, and immediately were paid Zimbabwe dollars 185 (when the local currency was equivalent to British Sterling 2.00) a month for two years.

She detailed the “many, many agencies” that ‘”poured millions of dollars” into schemes to assist ex-combatants. She went on: “It can be safely said that no other group in this country has since independence received greater assistance than the ex-combatants.

“A war affects everyone, particularly in the rural areas. It is not helpful … to assert that one group (war veterans) is more important than any other. This leads to ex-combatants believing years after conflict has ended that they still have the right to special resources from the state.”

Last week an official of the war veterans’ association declared that it had registered 34,500 veterans, meaning that since 1981, only 6,500 have died. It suggests that the group has passed through the AIDS epidemic, chronic hypertension and diabetes virtually unscathed. Youths who were 18 when they joined the movement immediately before independence in 1980, would be 54 now. A major chunk of the war veterans who joined earlier and when they were older than 18, could be expected to be well into their seventies now.

Tendai Biti, the pro-democracy MDC party’s minister of finance in the 2009-2013 coalition government, was responsible for budgets that included drafting assessments for war veterans’ pensions. He scoffs at the association’s figures. “There couldn’t be more than 15,000 now, according to my calculations.”

Whatever the difference between the two figures, Biti says, “the irony is that as war veterans disappear and die of old age, the budget (for war veteran pensions) is increasing instead.”

Figures published annually in the government’s budget provisions show that in 2010, the amount set aside for war veteran pensions was US$58 million. Five years later the figure had increased to US$105.5 million – an increase of 45 percent.

“We now have war veterans who are 25 years of age,” said Biti. ”The challenge is that the process has been corrupted by shadowy elements who have been added to the list. The whole system needs thorough vetting.”

The previous chairman of the war veterans’ association was Jabulani Sibanda, a youthful looking man who would never tell reporters when he was born. Investigations published in the local media reported that he was 10 when the war ended.

The veterans appear now to be shifting out of favour, as political tremors begin to shake Zimbabwe’s political landscape as never before and fissures in the ruling ZANU(PF) party widen. And the principle cause of the disturbance is Grace Mugabe, the president’s 50-year-old wife. At his advanced age, coupled with frequent secret visits to a hospital in Singapore in the last week, discussion of his likely successor has become more heated than ever.

The war veterans, in common with most of the country, dislike her for her arrogant, loud and charmless manner, and say so. “It’s clear now that the country is being run by whores and gays,” a veteran shouted as riot police descended on them in February. “Who is Grace?” demanded another. “There is no first lady in the constitution. We want the president to come clean on this.”

Mugabe has repeatedly defended her, condemning “this trend these days where … people in the party disrespect the party leadership, insulting even my wife, the wife of the president!”

But the fundamental reason underlying the veterans’ hostility towards Grace is that the movement is regarded as among the most important backers of vice-president Emmerson Munangagwa in his pursuit – which he fiercely denies - to succeed Mugabe. And Mugabe - though he also denies it - is seen as carefully grooming Grace for the job.

The war veterans are the only group in the country that doesn’t kneel at the feet of the president. The past few weeks have seen them sniping openly at the “the first family.”

When this week’s meeting was first mooted, the veterans insisted that the issue of Mugabe’s successor, as well as demands for fatter pensions, was on the table. Statements from Mugabe’s office do not refer to the political business, but only to their pensions.

It will be a strenuous test on Thursday for the aged Mugabe to face and win over the war veterans. Rather than trying to bully them into silence, he is likely to use bribery, with vastly increased gratuities from the country’s forlorn fiscus.

The veterans want Mugabe to make a commitment towards stepping down, clearing the way for their unofficial patron, Munangagwa. They cannot be expected to sit mutely through a Mugabe diatribe. He will need all of what is left of his prodigious cunning to survive. The monster he created is ready to consume him.