The British auto industry today is facing one of its worst crises ever thanks to declining car sales and the uncertainty over Brexit. Global automakers have put off or canceled fresh investments, and invested instead in cheaper locations like Slovakia, while at the same time shutdowns or relocations of existing plants are imminent, according to experts. Layoffs have already begun in the industry, with the U.K.’s biggest automaker, Jaguar Land Rover,  announcing  4,500 layoffs, or more than a tenth of its 40,000-strong workforce. The country’s auto industry at last count employed 860,000 people, which includes supporting segments such as repairs and financing, generated 82 billion pounds ($108 billion) in annual revenues and had an economic impact of $266 billion, according to data from the Society of Motor Manufacturers and Traders (SMMT), the trade body of the U.K. automotive industry.…