On Monday, the South African president, Jacob Zuma, once again went to Tripoli in an attempt to broker a peace deal between Colonel Muammar Gaddafi and the opposition forces. As expected, he failed. But mediation or ceasefire initiatives such as South Africa's, and others encouraged elsewhere, have something wrong with them: they offer Gaddafi a lifeline at a point when he is facing an increase in defections and significant opposition progress on the battlefield, and when he is becoming increasingly isolated internationally – as shown last week when Russia shifted its position by calling on him to stand down. It is clear that the west, in the form of the Nato-led coalition, has a strategy in Libya and it is working. It should be left alone. Three key components have comprised this strategy, the explicit objective of which has been to end Gaddafi's reign of terror and the heart of which has been to ensure the Libyan uprising remains a Libyan-dominated enterprise, and not a western one. First, western military strategy has, at the outset, been to hit Gaddafi, give the opposition a chance to progress and then hit the regime harder where progress was insufficient. As part of this effort, rather than utilise its military capacity to full effect, Nato has limited its engagement to a gradual process of intensification, an approach that ensures progress – and, indeed, western involvement – depends on the efforts of Libyans on the ground. For example, since the start of its operations in Libya three months ago, the west has resisted repeated opposition demands for attack helicopters. I was witness to these desperate calls in Benghazi when, in a meeting, one senior opposition official called on the British envoy to Benghazi, Christopher Prentice, to deploy attack helicopters that could accurately and effectively attack regime targets. Three months later, and after massive civilian casualties in besieged Misrata and other towns and cities in western Libya, the west has only just decided to deploy these helicopters, but at a point when a more organised and effective opposition army has made good progress and is now capable of making further progress on the battlefield. Alongside training and advising opposition forces, the third key and under-appreciated part of this strategy of gradual military intensification has been the encouragement of political and military defections and, therefore, the crumbling of the regime from within. It is working. The latest high-profile defection to further demoralise the regime was that of Shukri Ghanem, the regime's oil minister and former prime minister. He was followed by the defection of eight Libyan army officers, including five generals, who were part of a wider group of 120 military personnel that defected in recent days. Nato must as a result continue its job and work in tandem with and at the behest of the Libyan revolutionaries. In fact, it will do well to consider formulating its current strategy into a benchmark for future military engagements – a strategy based not just on working in partnership with indigenous populations in the fight against dictatorship but also, first, their own capacity to fight and, second, efforts to train and possibly arm them when necessary. Conversely, calls for a peaceful settlement with Gaddafi and his inner circle, made simplistically without any serious effort to define its terms, make no helpful contribution. The most a ceasefire proposal can call for is a transitional, face-saving process that brings Gaddafi and/or one of his sons, along with the opposition, into a power-sharing arrangement that, at best and at some point, leads to elections. As well as the array of problems likely to follow – including Gaddafi using the opportunity to reorganise himself and consolidate his position, as well as the bloodbath that will ensue in prison cells and far-flung compounds that the west will never know about – any such proposal would require mediation and monitoring by outsiders in the form of the UN and potentially the African Union. It would also require a sizeable ground force to ensure both sides commit to the ceasefire and that there is an effective keeping of the peace. That, however, would diverge from the lessons learned from post-conflict management in Iraq: any peace proposal that operates around conditions laid down by outsiders, and not Libyans, will be tantamount to an international trusteeship that will open up a Pandora's box of problems. For example, proponents of a negotiated ceasefire do not explain how regime loyalists should be dealt with as part of their grand plans or, more problematic still, what "monitors" would do if loyalists or anti-regime opposition forces are hunted down and killed systematically in a manner similar to post-2003 Iraq. It is these realities that have to be considered when making calls for a ceasefire, which is right in principle but reckless in practice. Nato should stick to its strategy, one that will eventually encourage other hardline regime elements to force Gaddafi and his sons out or, alternatively, force Gaddafi to accept that he is fighting a losing battle and flee the country – but only once the opposition comes knocking on the doors of Tripoli. It is toward this objective that Nato and the international community should aim, since it is only once the opposition is on the brink of embarking upon and liberating Tripoli that the Gaddafis and their inner circle will accept their fate could be determined by their enemies. Either way, it is Libyans who must choose how this conflict will end.