On 26 February, the UN Security Council passed a hard-hitting resolution designed to send a clear message to Muammar al-Gaddafi and his regime. As well as an asset freeze, travel ban and arms embargo, the UN took the unprecedented step of requesting that the International Criminal Court (ICC) investigate possible war crimes or crimes against humanity committed by Colonel Gaddafi and his forces.

Such a resolution might be expected to persuade most sane leaders to desist from extrajudicial killing, but Colonel Gaddafi is not your average leader. Several days on, it seems that not only did the message fail to stop the violence, but that it may be having the opposite effect, persuading members of the regime in Tripoli that they have no option other than to fight for their survival.

With the attention of the world focused on North Africa and the Middle East, the escalating violence in Libya presents a very public test of the international community's commitment to prevent crimes against humanity. With calls for international action becoming louder, the UN Security Council was stirred into action, passing a landmark resolution, the first of its kind to make unambiguous reference to the principle of "responsibility to protect".

In 2005, following its failures in Rwanda and Kosovo, the UN General assembly adopted the principle of "responsibility to protect", intended to provide a new level of international consensus that would allow swift action to prevent future atrocities. However, repeated failure to intervene in places such as Darfur, the Democratic Republic of Congo and Sri Lanka, combined with widespread post-Iraq cynicism toward all forms of so-called humanitarian intervention, suggested the principle might never be put into practice.

And then along came Libya.

While it was always unlikely that Gaddafi, who had already announced his intention to "fight until the last drop of blood", would be unduly bothered by a threat of referral to the ICC, it was hoped that members of his regime – most significantly the military – might take this loss of impunity more seriously. Indeed, Resolution 1970 allows for individuals thought to be responsible for attacks against civilians or human rights abuses to be nominated for addition to the ICC's charge sheet.

But, rather than encouraging the military to turn on Gaddafi, generals and soldiers who had already been involved in putting down the protests may well have been forced into the same "last stand" mentality as their leader.

This is not to say that Resolution 1970 was unwelcome, nor that the principle of responsibility to protect is unimportant. The international community should have an obligation to step in where states manifestly fail to protect their populations. The asset freeze and arms embargo will impact on Libya, but their effect will be slow and experience has shown that sanctions may cripple a nation without necessarily bringing down its governing regime.

Despite Robert Gates's description of it as "loose talk", contingency plans for some form of military intervention are no doubt being drawn up. The imposition of a no-fly zone would need to be authorised by the UN Security Council, and this is looking more possible following the recent shift in the French position and support from the Arab League. Whilst a no-fly zone would not prevent killing on the ground, it would stop aerial attacks by the Libyan air force and prevent weapons and other supplies from reaching Gaddafi's security forces.

The current situation in Libya remains turbulent and unclear. There are indications that a UN humanitarian team may be allowed into Tripoli, but in the meantime the violence continues. As each day passes and more blood soaks into the sand, the harder it will be for a post-conflict Libya to put itself together again. Bloody internal conflicts – be they in Iraq or Rwanda, Yugoslavia or Indonesia – leave indelible scars on nations and festering resentment among their populations.

The international community may struggle to find consensus as to the best way to prevent further bloodshed in Libya, but whatever action or inaction they choose, will be watched carefully by policymakers and dictators around the world. The success or failure of international action on Libya will no doubt shape future forms of humanitarian intervention and help determine how the principle of responsibility to protect can be put into practice.

Stefan Simanowitz is a journalist and Middle East/Africa analyst.