When the army moves into 10 troubled Cape Town neighbourhoods it will calm things down, as it did in 1998. But it’s a temporary band-aid on a problem which lies elsewhere. When they leave, if they can, the violence will bounce back, as it did then. There are several reasons why.Firstly the gangsters with guns and drugs they seek are the visible part of an extremely complex underworld which includes foreign transnational smugglers, local warehousing merchants, area syndicate bosses, gang bosses, bent cops and young street 'soldiers' who are the ones who generally pull the triggers. These are beyond the scope of the army – and seemingly the police – to control and will be there when the army leaves.There are 'warrior' gangs like the Vatos and Vuras who fight for status, merchant gangs who fight for territory, big gangs like the Hard Livings and Sexy Boys who fight to control supply routes and sales turf, small corner gangs who fight for the right to be on their corner, girl gangs, fierce prison Numbers gangs and 'baby' gangsters who seek to emulate their older brothers.If you eliminate a street-corner gang fighting (and killing) over market space, others will simply take over their sales turf – basically widening opportunities for others. The army would be mopping up water when they should be turning off the tap.Why has it come to this in one of the world’s most beautiful cities? Much of it stems from the way this country has treated its young people.The type of education they receive in most township schools does not provide huge numbers of them with the interest and skills to create a profession or land a paying job. Half the people who begin school drop out before matric.At last count there were 350 000 youths under the age of 25 in the city not in education, employment or training (NEETs). They are literally on the streets.A high number of those would come from families damaged by apartheid relocations, migrancy and high levels of alcohol use. The problems start early. In the Western Cape, 16% of women were found to be malnourished, 16% anaemic, 5.7% had iron deficiency, 41% had a low vegetable intake. This can have a negative effect on an unborn child.Several studies have found that poor foetal growth and stunting can lead to cognitive impairment. Add the mother's use of alcohol or drugs and there's a high possibility of irreversible brain damage.These problems lower a child's ability to cope with both school and social conflict and may be implicated in the development of aggressive, violent and antisocial behaviour. So control problems happen long before gangs get out of control.Another problem is drugs. Some governments, such as in Brazil, Honduras and Mexico, pursued paramilitary responses to gangs and the drug trade. These operations have mostly been counter-productive, escalated existing violence and provoked further bloodshed. There have also been accusations of brutality, human rights violations and corruption.In 2011 the Global Commission on Drug Policy declared that the 'global war on drugs has failed, with devastating consequences for individuals and societies around the world'. One solution is to decriminalise drugs and place their regulation in government hands, as Portugal has done very successfully. Then crack down on drug syndicates – many of them foreign.There are other interventions which, though not as dramatic as troops in townships, have a far greater potential for success. These include a widespread campaign against the use of alcohol during pregnancy, nutritional support for pregnant women and professional help with their children in the first 1 000 days of their life. It also requires fathers to step forward as role models for their sons, appropriate skills-based training and more jobs. And an education system that really educates.The most successful international gang violence interventions focus on targeted community-police violence prevention partnerships in gang neighbourhoods. The logic is that because gangs are deeply embedded in certain communities, it's within these communities that appropriate solutions to the violence should be found.Police have also realised that they can only have a positive impact on gang violence when community members consider them to be legitimate.So while there are many who quite understandably welcome the deployment of the army in their troubled areas, unless the use of soldiers is very strategic and carefully planned, it may be difficult to let them leave for fear of renewed killings.That could escalate violence and collateral damage. To a soldier with a gun, it will be hard to tell the difference between an enemy and a bunch of friends hanging out on the street corner. The crossfire youths already have to deal with could now come from two directions. That would add unbearable pressure to all young people trying to get by in those areas.*Dr Don Pinnock is a criminologist who has written extensively on gangs in his books Gang Town, Gangs, Rituals & Rites of Passage and The Brotherhoods.