US President Barack Obama produced no surprises in his landmark speech, which focused on the military alliance of international and Arab states that is mustering to take on the Islamic State of Iraq and the Levant (Isil) through a combination of air strikes, ground forces in support of Arab forces and intelligence work.

It is a problem that he was almost totally silent on the final political objectives of this war, and he will need to spell these out more clearly. But it is very welcome that the Americans are taking a lead in combating the threat from Isil terrorists, and it is also important that they are working with the Iraqis and other governments from the region. Without such a broad consensus from the region there is no hope of turning a possible military victory into a long term political success.

It was also very important that Obama was firm that the US will not work with the Syrian government, and will seek Congressional authority to work with the Syrian opposition as a counterweight to the extremists in Isil. There was a worrying perception growing that the US will work with any general who can command troops and impose stability, so it was heartening that Obama made the decision that the US can never rely on a Bashar Al Assad regime that terrorises its people, and will never regain the legitimacy it has lost.

As the president sent his officials all over the Middle East to find Arab nations who can help mobilise the Sunni communities in Iraq and Syria to drive Isil from their lands, he produced classic Obama rhetoric when he said: “This is American leadership at its best: we stand with people who fight for their own freedom; and we rally other nations on behalf of our common security and common humanity.”

The problem is that we all heard this before when the Americans first went into Iraq and created the civil war that built the divisions with which we are now living. What Obama needs to do is make clear why his offensive will be different, and how it will build a lasting political structure that will help create a permanent peace.