A "commando" in American English is an individual highly trained military expert, capable of operating on his own with very little direct supervision nearby.
A "commando" otherwise means a small-to-middling sized military GROUP, larger than a platoon, say perhaps a hundred to a few hundred men, operating on its own [at the moment] rather than as part of a larger army.
If you want to read more about the brave Air Commandos, Orr Kelly's book "From A Dark Sky" tells their daring deeds from Burma during WWII through Vietnam to Desert Storm. Awesome read, some of the stories you just shake your head.