Each branch of service is the best of the field at its own forte, Marines and Army do not do exactly the same thing though both are (In their own ways) in the ground combat business. Each branch does an at-par-but-not-exceptional to inferior job of imitating another when it is cast in a role outside its main strength.
I like the Marines I've known and of course we rag each other, but just as they'd rather other Marines had their back, for Army main-line missions I'd a lot rather the Army had my back. There's great mutual respect under the jibes, but in the real military world you always, always have to remember 'They' are not 'Us' and 'They' bring a whole different set of strengths and weaknesses to the table (Or on board, as the case may be) failure to recognize that will end up in a lot of the wrong people getting killed.
