How the mighty fall. For decades, the self-appointed saints of our secular age bestrode the world, preaching happily to the converted about their good deeds and miraculous impact on the poor. Few dared to criticise them for fear of being branded selfish. Yet now the arrogance of the aid industry lies exposed after revelations about abuses of power and desperate efforts to protect its flows of cash.

These are sad days for aid workers whose genuine desire is to do good. But we are seeing a glimpse of the corrupt mentality, dubious morality and money-driven mindset that plague a sector posing as saviours of the distressed and dispossessed.

This has been seen in the harshest glare with distressing details of sexual abuse and cover-up swirling around Oxfam. This group deserves all the flak it is taking, despite bleating from its beleaguered boss over the intensity of fire.

The shocking recent allegations of sexual abuse and the cover-ups at aid agencies have exposed the industry's arrogance

This is an organisation that built its brand hyping famine in Cambodia and last month issued a flawed report into global inequality when it hands its United States boss more than half a million dollars a year, placing him in the richest 0.1 per cent.

Alas, such hypocrisy is all too common, as I have discovered over a decade investigating the bloated aid sector across the world. Even that mega-salary is far from unusual in the poverty industry. Take one small example: it is no surprise to learn that Oxfam’s US communications chief takes home more than £210,000 a year, nor that there are more than 20 public relations officials in the UK branch but just four dedicated to safeguarding against abuse.

For behind a virtuous veneer, many of these huge charities have become self-serving corporate brands that suck up cash from good people wanting to make the world a better place, assisted by gullible politicians trying to look compassionate.

Oxfam’s US communications chief takes home more than £210,000 a year, something that does not surprise anyone

Why does a failed politician such as David Miliband need £479,000 to run another leading aid outfit? Why does Save The Children International, bragging of contracts worth £91 million from the Department for International Development (Dfid) in 2016, need more than 55 staff at its London base on six-figure salaries?

Would these people who constantly beg for funds from grannies and governments, and who are often far from the front line, not do these jobs without lining their own pockets a little less?

After their successful promotion of an absurd aid target for governments – that prioritises spending over need at a time when global poverty has never fallen faster due to capitalism, science and technology – money is flooding into this sector.

Two respected academics have calculated that the global poverty gap – the amount needed to push the entire global population over the poverty line – is £47 billion. Yet across the world, more than twice this amount is spent annually now on ‘development’ aid. So as surely as night follows day, these charities have been joined by a swarm of private operators chasing the swelling tide of cash, and billions are blown each year on vainglorious projects that hinder rather than help development.

I exposed in this paper how Britain’s biggest specialist operator, Adam Smith International, attempted to mislead MPs probing excessive pay and profits in the sector while engaging in dirty tricks to help win state contracts.

The Oxfam scandal and the stunning allegations about aid agencies is at heart about powerful people abusing trust

Much of this money sloshing around the globe simply makes rich people richer. It entrenches bloodstained regimes in power, undermines democracy, worsens corruption and fuels conflict by freeing up state cash for arms. I have heard the crescendo of complaints on three continents. Nana Akufo-Addo, Ghana’s president, is among influential voices demanding Africa moves ‘beyond aid’, rightly arguing it has failed to deliver growth and creates a dependency culture.

It was no surprise to see Haiti at the heart of the Oxfam scandal. For this blighted nation symbolises the shameful failure of both humanitarian and development aid.

There should not just be fury over the abuse of some Haitian women by a handful of Oxfam officials and World Vision workers. There should be deep and profound anger over the abuse of an entire nation by the greedy, incompetent, patronising and predatory aid industry.

Even before the devastating 2010 earthquake, there was one charity on the ground for every 900 citizens, and it received huge sums in aid – while average income fell by more than one-third.

Then the earth shook for 35 seconds, killing more than 200,000 people. Billions was pledged in aid but much of it sat gathering interest in bank accounts or was squandered on staff expenses while suffering people remained stuck under plastic, local voices were ignored and the United Nations imported cholera that killed thousands more people.

One senior official I met in Haiti spoke candidly about the allure of staying in a swanky villa with a pool, driving around a disaster zone in a new four-wheel drive vehicle with free meals, an armed guard and a halo. ‘It’s cool, it’s fun and sometimes you even help people,’ he said. ‘But more often you end up wondering if you are really making matters worse.’

The Oxfam scandal is at heart about powerful people abusing trust, whether on the ground with prostitutes in Port-au-Prince, or in the offices of London by attempting to protect their brand above everything else to keep donations flowing.

It stands as a perfect metaphor for an ideal that has been corrupted by cash, for benevolent institutions that have been corroded by power and, above all, for people with good intentions who arrogantly refuse to recognise an uncomfortable reality.