He has already said that he has made up his mind that the attacks were carried out by the Syrian government under Bashar al-Assad, and not al-Qaeda elements among rebels or the CIA covert operatives skilled in framing others.

The mask of difference between George W Bush and Obama has now been removed. That began with the manner in which he prosecuted – with the precision and subtlety that the drone campaign represents – Bush’s war on terror, succeeding in killing many al-Qaeda elements and also hundreds of civilians in the process. If the US posture under Bush was what has been called humanitarian militarism – the idea of bombing “enemies” and civilians on the pretext of saving them from their own governments – then Obama has perfected it, being able to do it without committing troops on the ground, using war technology (the drone) and with a likeable smile. Concern for the plight of Iraqi civilians, like that of Libyans recently and now Syrians, is useful for the justification of regime change.

In a sobering analysis of humanitarian militarism published recently, Maximilian Forte makes the point that it thrives on the ability of the powerful to directly and indirectly create a sense of the suffering of others, seeing every outstretched hand as pleading for help or welcoming “the humanitarian intervention”.

In this sense, the powerful draw their moral might from the physical plight of others. In this humanitarian story, the powerful are not their brothers’ keeper, as the information campaign suggests, but they are their “animal keepers”.

For, Forte shows, “Bombing for us is really just an animal management technology, and our relationship to the world remains a zoological one”.

In this way, Assad and his government are regarded as being in the zoological zone, the realm of non-beings, thus qualifying for bombing to free civilians they have trapped under their claws.

As we saw in Libya, some Syrian civilians also qualify for the non-human zone by virtue of their being seen to be on the side of Assad; they are called “human shields”. Like perimeter walls of the Syrian army headquarters, they are shields with a human appearance. In this scenario, the bombers are liberators.

In the process, the international community is replaced by a coalition of the willing, made up of a coterie of clientele states, some with terrible democratic records.

The UN is included if it allows itself to be party to the “humanitarian intervention” but, as we see with the imminent strikes on Syria, the UN can also be ignored and denigrated.

The US government has already poured cold water on the expected report of the UN weapons inspectors, who have just concluded investigations of the chemical attacks in Syria, because it believes its own information, wisdom and voice.

It wishes that we should not recall the scandal of previous US “intelligence” about weapons in Iraq and Libya that came to naught. In humanitarian militarism, the end-goal is not stated, but it is generally known. It is regime change and defence of Western hegemony.

John Kerry told the Senate Foreign Relations Committee hearings this week that the US was not planning regime change, but if it happened it would be welcomed.

Officially, the aim is to diminish the military capability of the Syrian regime, thus changing the balance of power in a civil war in favour of the opposition.

Kerry admits that he does not know the power of extremists, so-called jihadists and al-Qaeda elements within the armed opposition.

The possibility of the US strikes abetting al-Qaeda is conveniently ignored. The possibility of the “limited strikes” simply deepening the military stalemate internally, prolonging the civil war and worsening the suffering of Syrians, is denied.

US strikes on Syria will violate the humanitarian rights of some, while ostensibly protecting those of others. The endgoal – regime change – falls outside the common purpose of the international community. It is to be executed without UN approval. It is thus a violation of some international norms – of UN sanctity and multilateralism – while purporting to be in defence of another one, the prohibition of chemical attacks. It promotes the rule of the jungle in that in the end it is about “might is right”. It divides rather than unites the international community.

In this sense, what Obama is about to do is illegal, falling outside the ambit of the UN, and morally indefensible in using the plight of others for hidden political ends that are undemocratic in their essence.

It will subvert the right of the citizens of Syria to change their own government.

The ease with which Obama is embracing war to deal with essentially political problems is baffling. The US cannot prove that it has supported political solutions led by Kofi Annan and Lakhdar Brahimi as UN special envoys.

They have both pleaded against further militarisation of the conflict by Western supply of arms to the Syrian opposition. The US has subverted these efforts by giving hope that a military solution is possible.

The use of chemical weapons against innocent Syrians is a terrible crime. But it is for the UN to investigate the incidents to enable the community of nations to identify culprits and decide on proportionate punishment. No country should arrogate to itself the role of global policeman. No amount of internal disagreement within the Security Council takes away from the UN its legal role as a guardian of international law and norms.

It does not make sense that the US would this time to be on the side of socalled jihadists in the battle for the control of Damascus and thus harm its image as a democracy and a force against terror.

History will judge Obama as having failed to show the audacity of hope that he speaks and writes about so eloquently to prevent further civilian suffering. He has instead chosen the arrogance of might.

He is on the verge of soiling the legacy of Martin Luther King jr and Nelson Mandela that he benefits from, as well as the peace movement behind his electoral victory by choosing the ego-politics of his nation over world peace.

South Africa and global peace movements are right to warn about the unintended consequences for world stability, economic recovery and the UN’s sanctity.