I would have thought that the Glasgow Police Force [who have successfully managed security and crowd control etc. at
OLD FIRM matches for decades] will play a very big part in the overall security of the Glasgow Games.
All of the big football stadiums [and their outlying environs], including Hampden Park, Ibrox Park (Rangers) and Celtic Park
(where the opening Commonwealth Games ceremony will be staged), are familiar 'stamping grounds' to the local police force as far
as crowd control and security is concerned.
G4S or The Army will only be a hindrance to them, I reckon.