If Turkey agrees host nation support and basing for coalition forces, this could give not only a shorter round-trip for our fast jets, it might also allow the deployment of attack helicopters and perhaps even air- mobile ground forces. These would offer the potential for greater military effectiveness together with a lower incidence of collateral damage (which is essential for continued political effectiveness).
We must, however, resist pressure for the sort of moves against Bashar al-Assad which the Turks may wish to see (except as a limited response to specific violations).
We can be in no doubt about the consequences of creating a power vacuum. It would be wildly optimistic to assume that efforts towards a democratic alternative will not now result in an Islamist takeover.
Unpalatable as many find the continuation of the Assad regime, the cost in lives and suffering of the war to overthrow it already greatly outweighs the benefits of succeeding.
The displaced people of Syria deserve peace much sooner than we can possibly conjure up some replacement with which we feel more morally comfortable.