Dr Martin Parsons is a former aid worker in Afghanistan and Pakistan.

It may have gone largely unnoticed, but the Conservative manifesto makes a radical new commitment to overseas aid. The Prime Minister gave a distinct hint of this change in a speech last month when she said: “Let’s be clear: the 0.7 per cent remains and will remain. But we need to look at how the money is spent and make sure that whatever we spend is done in the most effective way.” That hint was reiterated in the manifesto commitment, which said that the UK should exercise: “Global leadership on development, backed by spending 0.7 per cent of our national income with new rules to spend it more effectively.”

It’s that last bit which is so radical, and has the potential to make UK aid so much more effective. Let me explain. Back in 1969, the Pearson Commission recommended that countries spend 0.7 per cent of their GNP on aid – and took a fairly restricted view of what constitutes aid spending. The 0.7 per cent figure was based on an estimate of how much money developing countries then needed to catch up with the developed world. In other words, the Commission saw a lack of money as the primary cause of underdevelopment.

Since then, development thinking has moved on by light years. There are a whole variety of different causes of poverty, and effective development requires action not just at local, but also national and international levels.

Take Afghanistan – where I was an aid worker during the time of Mujuhaddin, Taliban and post 9/11 governments. The country was bottom but one of virtually all development indices. Some of the problems could be solved with money and outside help – such as providing basic health care and irrigating land, so that people could grow enough food to feed their children.

However, the greatest cause of poverty was the civil war between mujahaddin warlords and then the Taliban. It was only after the post-9/11 western intervention that investment started to flow into the country and jobs began to be created which might, eventually, produce enough of a tax base to finance health and education.

Government aid spending should complement the work of international aid agencies, not replicate it. There are some things that only governments can do, such as defence and the institution of a just, equitable and impartial system of justice. In fact, if anyone other than the government in question tried to undertake these roles – as for example, various warlords in Afghanistan did on both counts – then, by definition, that country would be a failed state.

This is why Tony Blair got it so catastrophically wrong in 1997, when he separated off UK aid from within the Foreign Office, and made it an independent department. This took away from the Foreign Office one of the most important aspects of ‘soft power’, leaving it with not much more than diplomacy – i.e. ‘talking’ to deal with abusive governments. It also led to the assumption that government aid was simply ‘aid agency spending writ large’, rather than the two having largely complimentary roles.

One of the most extraordinarily effective examples of UK government aid occurred in the summer of 2014. As Islamic State forces surged eastwards and seized Mosul, they also surged westwards and sought to cross the border into Lebanon. Had they succeeded, they would they would almost certainly have carried out the sort of atrocities they were committing in Syria and Iraq.

The reason they didn’t was that, following a request from Najib Mikati, a former Lebanese Prime Minister, to David Cameron, a British team had worked 24 hours a day to construct a series of fortified watchtowers along the border. At Ras Baalbek, the watchtower literally saved the town’s predominantly Christian population from the sort of massacres being carried out on Christians and other minorities in Syria and Iraq. Less than a fortnight after its completion, IS tried to invade. One of the UK construction team described how: “When the invasion came, a line of vehicles split off and headed for Ras Baalbek…Then they stopped and looked up at the watchtower and all its artillery waiting for them. They turned around.”

It was not just one town that was saved. Since the end of the Lebanese civil war in 1990, the country has been a delicate balance of Sunni, Shia, Christian and Druze. The UK’s then ambassador, Tom Fletcher, suggested that if the fort had not been built in time at Ras Baalbek, the whole of Lebanon could have descended into a new sectarian conflict.

The cost of welding those few shipping containers into a watchtower at Ras Baalbek must count as one of the most effective pieces of UK assistance to another country, saving countless lives and untold suffering that would have resulted from war in Lebanon.
However, according to the definitions of aid spending used since the Pearson Commission, it didn’t count as ‘overseas aid’.

That is why it is so significant that the Prime Minister has made a manifesto commitment to seek international agreement on a redefinition of these rules. That doesn’t for one moment mean that the aid budget is going to be used to shore up the defence budget. The manifesto commitment is clear that whatever the aid budget is used for, it has to be in line with the sustainable development goals. However, what it does do is aim to to lift a straitjacket that has confined government overseas aid since the 1970s.