Battles in Ukraine, Gaza and Syria have appalled all who watch them from afar. The effects on the young provoke much of the horror. But many other armed conflicts are occurring, often far less visibly, in developing countries — and these are also home to the world’s highest populations of children and young people.

Under-18s are described as requiring special protection in times of war in the United Nations Convention on the Rights of the Child, which celebrates its 25th anniversary this year. The convention, although lacking the teeth of enforcement, has provided a framework for discussions and planning that has spawned useful research. That research has begun to identify what ‘special protection’ really means — and the amount of time and resources it demands.

For a country to recover from war and rebuild a functional society, its young generation must be physically and mentally fit. In the past decade or so, humanitarian organizations have become increasingly aware of the prevalence of mental illness. This is particularly relevant for children and adolescents, because research has shown beyond doubt that prolonged and severe stress can damage the developing brain. Poor countries, often confronted with life-threatening epidemics of infectious disease, are too often unable to make mental illness a priority. But they surely need to embed in their health-care systems mental-health strategies for helping their traumatized youth.

Researchers, often supported by humanitarian organizations, have already undertaken scores of field studies in countries damaged by war or natural disasters. From Africa to Indonesia to the Balkans, they have tried to work out which interventions could help to mitigate or avert the mental damage caused by severe stress. Common inter­ventions involve structured individual or group psychotherapy based in schools, for example, or family counselling.

As one might expect, the quality of societal support — an intact family, a trusted care-giver, a protective neighbourhood — has a major impact on whether an intervention will help. Still, many children emerge from trauma undamaged, even without an intervention. And an approach that works well in one context may even be harmful in another; for example, some displaced boys in Burundi responded negatively to a type of psychotherapy that had proved helpful in Indonesia.

There can be no single approach to limiting the mental damage inflicted by war. To be useful, interventions require intense engagement in the life and experience of each individual. For example, when working in Bosnia in the 1990s, a US psychiatrist discovered from conversations with one boy in his study group that, to get to school, the boy had to pass the tree from which he had witnessed his brother being hanged. It was helpful to bring this nightmare confrontation into their therapeutic sessions.

Worryingly, new scientific results are not getting through. Many popular therapeutic approaches — family counselling, for one — have not been rigorously tested in post-conflict contexts. And psycho­therapy, known to be effective in post-traumatic stress disorder, is rarely practised, in part because of a lack of capacity to deliver it.

Humanitarian organizations, for all their importance, might not leave conflict zones with sound infrastructure. This underlines again the need for countries to develop their own scientific and medical capacities.

Immediate interventions in schools make sense, because rebuilding a society requires an educated next generation. But many more longitudinal studies are also needed to track traumatized children into adulthood, to see if and how the treatment they received helped them.