Delves was appointed the British representative to United States Central Command in Tampa, Florida for the War in Afghanistan on 17 January 2002. While at Central Command, American General Tommy Franks oversaw the military effort against al-Qaeda in Afghanistan. Delves had succeeded Air Marshal Jock Stirrup as focus changed from air operations to a campaign conducted largely by special forces on the ground. This appointment was just prior to the Invasion of Iraq, and Delves went on to be Deputy Commander at NATO HQ Allied Forces North at Brunssum in September 2003. On 31 December 2002 he was appointed Colonel of the Devonshire and Dorset Regiment. He was knighted as a Knight Commander of the Order of the British Empire in June 2003 and, on 1 October, was succeeded as Colonel Commandant of the Small Arms School Corps by Lieutenant General Sir Redmond Watt, Delves having been appointed Deputy Commander-in-Chief Regional Headquarters Allied Forces North Europe on 30 September 2003.