Tea versus Coffee

The past 10 or 20 years have seen our national drink, the calming, soothing cup of tea, ousted in favour of the nerve-jangling, palpitation-inducing coffee, as a result of the remorseless spread of coffee chain emporia such as Starbucks. Is it merely a coincidence, then, that this same period of time has seen a marked deterioration in the nation's civility and good manners?