It was a bad idea when Labour introduced this and it's no better under the Conservatives. Besides being intrusive for the people of Great Britain, it's also painfully difficult to troll through that much data with much effectiveness. The Guardian:
Ministers are to introduce a new law allowing police and security services to extend their monitoring of the public's email and social media communications, the Home Office has confirmed.
It is expected that the new system will allow security officials to scrutinise who is talking to whom and exactly when the conversations are taking place, but not the content of messages.
Labour tried to introduce a similar system using a central database tracking all phone, text, email and internet use but that was ditched in 2009. It followed concerns raised by internet service providers and mobile phone operators over the project's feasibility, and anxieties over who would foot the bill.