Last time of saying this... I wasn't a contractor!
I think there is more of a problem with semantics here. 'Contractor' in this sense doesn't necessarily mean 'self employed'.
There are various contracts for companies to provide various services to British forces or the British govt in Iraq ranging from security to IT to catering. The people employed to fulfill those contracts are often referred to 'contractors'.
If you really were not a 'contractor' in that sense then can you clarify what you were - civil servant etc...?