What if there had been no United Nations resolution on Libya and no airborne attacks? Probably Colonel Gaddafi would have crushed the rebellion and punished his enemies by death or by imprisonment and torture. And then what? This further question is the important one.
Had nothing else been going in Egypt on one frontier and Tunisia on the other, or in, say, Yemen further away, or even in Syria, then Colonel Gaddafi's opponents would probably have packed it in. What encouragement would there have been to start again given the severe penalties for failure? That was the conclusion drawn in eastern Europe after the Soviet Union brutally put down revolts in East Germany (1953), Poland (1956), Hungary (1956) and Czechoslovakia (1978). But in the contemporary Middle East, there is something else going on.
Perhaps in a day or two, the repressive leadership of Yemen will fall. And so my guess is that the rebels, inspired by these nearby examples, would have made a second attempt, admittedly after a long pause to recuperate, to analyse mistakes and repair deficiencies as best they could and they might well have succeeded. For time would have provided no favours for Colonel Gaddafi, who would once again have become an international pariah.
Being a member of the brutally realistic school of diplomacy, I would have been content to wait hopefully for these developments. That is why I have not supported British intervention in Libya. For similarly unsentimental reasons, I argued in these columns against the invasion of Iraq. And, by the way, would those readers in favour of Britain getting involved kindly write to The Independent to describe what they would say to the grieving family of a British airman killed in action against Colonel Gaddafi.
The passing of the UN resolution that provides the legal basis for the action was solely the result of a humanitarian impulse. Only such a motive could have gained the support of the Arab League as well as the abstention of Russia and China. The argument "not to stand idly by" is powerful. However, a humanitarian impulse, whose normal outcome is acts of charity, is not an appropriate basis for going to war, however much we may wish it were.
That is why muddle and confusion have been the result. Earlier this week, US officials said that the heavy "front-end" of the intervention would soon be over, with the main objective achieved. But at the same time, William Hague, the Foreign Secretary, said that the "no-fly zone was in its early stages". The same divide shows up in the issue of whether Colonel Gaddafi should be specifically targeted. Those against include President Obama, who said that removing Gaddafi was not the military's mission. Robert Gates, the US Secretary for Defence, remarked that the US was anxious to avoid giving the appearance of seeking Gaddafi's overthrow, and the Chief of the UK Defence Staff, General Sir David Richards, observed that going after Colonel Gaddafi was not permitted by UN resolution. "Absolutely not," he added for emphasis.
In this, General Richards was contradicting his political masters. For Liam Fox, the Secretary of State for Defence, said it was a "possibility", and William Hague wouldn't rule it out. Even more remarkably, the Defence Minister, Nick Harvey, told the BBC that the deployment of British forces on the ground could be considered. He claimed there was a clear distinction between sending in a full-scale occupation force and a more limited operation.
Underlying these different interpretations of the UN resolution is the question of whether the purpose of military intervention is simply to protect civilians from attacks from the air by the institution of a no-fly zone, or to tip the conflict in the rebels' favour by securing not so much a no-fly zone but rather a no-drive area. British ministers are at the aggressive end of the argument.
Which is not where you find public opinion. A ComRes poll carried out for ITN found only 35 per cent said it was right for the UK to take action. Some 53 per cent said it would be unacceptable for British personnel to risk death or injury. In fact, Mr Cameron, Mr Hague, Mr Fox and Mr Harvey are curiously tone-deaf so far as these matters are concerned. The example of the Prime Minister's ill-considered arms-selling trip to the Middle East on the morrow of the successful outcome of the pro-democracy movement in Egypt shows this clearly. What British ministers are now saying to themselves is that, having obtained the UN resolution on humanitarian grounds, they would now like to use it as the basis for an intervention designed to bring about regime change.
If ministers are out of touch with public opinion, they also lack military experience. If they were better acquainted with the realities of the battlefield, they would be less gung-ho. Military experience fits into Donald Rumsfeld's "unknown unknowns". If you don't possess it, you don't even know what it is you are missing.
In the debate in the House of Commons on Monday, it was left to Kris Hopkins, the Conservative member for Keighley, in a speech that was considered the best of the day, to explain. He said: "I find it a daunting thought to be in the House debating and contemplating our responsibility for the deployment of people whose principal purpose is to kill other people on our behalf. During my basic training in the Army, I realised that a sergeant shouting at me to stab and scream and stab again a bale of hay with a fixed bayonet was teaching me how to rip somebody apart." And Mr Keighley reminded the House that "human beings need to commit brutal, savage attacks on each other to win wars".
I think the first thoughts of the Americans are right. Once Colonel Gaddafi's ability to wage war on civilian protesters from the air has been removed, then Allied forces should withdraw to the sidelines and be ready to intervene again only if Colonel's Gaddafi's air force shows signs of life. That would retain the assent of the signatories of the UN resolution and even the tacit approval of the abstainers. It would keep the Arab League on board. And it would satisfy British public opinion. If he goes further, Mr Cameron could suffer Mr Blair's fate and find a hasty retirement blighted by a foreign war.