LONDON — British dog owners may be forced to microchip their pets and take out insurance, part of a proposed crackdown on the country's dangerous canines. Postmen are delighted, but civil libertarians grumble that Britain's sprawling surveillance state now wants to track the nation's estimated 8 million dogs. Others complain that the insurance plan would impose a financial penalty on innocent pet owners – while criminals who own violent animals will simply shirk the law. "This is yet more surveillance and continuous data-grabbing by government who want to have as much information on us as it can possibly have," said Dylan Sharpe, a campaigner with privacy rights group Big Brother Watch.