Obama is right to sanction air strikes against Isis. Where the intervention ends is far less clear

It is strange to say it, but the residents of Erbil, in Kurdish Iraq, may be the lucky ones. The presence of an American consulate in the town in clear and immediate danger from the predations of Isis has placed all the people in the area under the protection of the US air force. Air strikes on Isis forces have been carried out, and more will no doubt follow.

Of course, President Barack Obama was right to take decisive action to save innocent people from genocide. Yet he and the world know that this is hardly a sustainable solution. Isis has conducted, in purely military rather than moral terms, an impressive series of victories against the larger Iraqi army, as well as several against the steelier Kurdish Peshmerga forces. Only now have the jihadis provoked swift action from Washington.

Would that such a rapid response had been available to the 40,000 Yazidi people now sheltering, if that is the word, on a mountainside, sustained only by Western humanitarian aid, or the Muslim and Christian peoples who have already been murdered and brutalised by Isis insurgents. The latest tragedy for Iraq – of many misfortunes – is that the civil war in Syria, MH17 and the invasion of Gaza have distracted the world from what is happening there, which otherwise would be at the top of the agenda.

It is difficult to overstate the scale of the disaster that is opening up. A stable, free Iraq was, after all, what thousands of American, British and other Western troops fought for, some making the ultimate sacrifice. It was what hundreds of thousands of innocent Iraqi people died for. The question unavoidably forms in Western minds: was it worth it? Did we deliver a more stable region, as George Bush and Tony Blair promised? Is Isis ready to send trained fighters back to Britain to carry on the jihad – something Saddam Hussein never seriously contemplated?

For those being tortured or driven from their homes by Isis, it is not immediately obvious that they have been liberated. We are, in short, looking at the final dissolution of the Iraqi state, and the creation of a new playground for terrorists every bit as dangerous as Afghanistan was before 9/11.

No one ever supposed that Iraq could be converted into a Middle Eastern version of Sweden. The “leadership” of Iraq since the American withdrawal, though, has beaten even the most pessimistic projections of its ability to govern competently and fairly. Even some of its best friends admit it has been nakedly sectarian in its approach, and its armed forces are evidently worse than useless, having abandoned and thus gifted sophisticated American weapons to Isis, which will now be using them to lethal effect.

It is now probably too late for the Iraqis to save themselves, and, as ever, American air support can deliver only so much. President Obama has ruled out “troops on the ground”. Withdrawing the US military from Iraq was meant to be an achievement on Mr Obama’s part. In days like these, he may be questioning its wisdom.