Obama's address showed a terror policy in transition – but had no quick answers

The most significant shift signalled by Barack Obama is towards a new understanding of the roots of Islamic extremist violence.

This is still a work in progress as the inconsistencies in Sunday night’s Oval Office speech made clear. But it could have powerful and important ramifications.

Most of the strategy to combat Islamic State outlined on Sunday night had been heard before in various formulations.

There was a further elaboration of the “slowly but surely” campaign to degrade and ultimately destroy the group. That degrading is significantly more likely than destroying is no doubt privately recognised by the president and his advisers but cannot be publicly admitted in the face of vituperative Republican criticism of the administration’s alleged timidity in the face of the threat Isis poses.