Brigadier Gordon Messenger said he did not recognise newspaper reports that quoted Royal Marines claiming high profile military gains were being squandered through lack of manpower and poor equipment.
Brig Messenger, who has overseen 32 British fatalities during his six months in command of 3 Commando Brigade in Helmand province, admitted they had "suffered setbacks" but said morale is good.
He was speaking as 122 service personnel returned to Exeter Airport, Devon, made up mainly of Royal Marines from 42 Commando based in Bickleigh, near Plymouth.
They were greeted by hundreds of family and friends who formed a cheering guard of honour to welcome them home.
Brig Messenger said: "I wont pretend that there have not been setbacks and surprises but the overall direction is one of progress.
"It is slow progress at times, but progress it is."