LONDON, Nov 17 (Reuters Breakingviews) – The British government has blocked the sale of a silicon wafer factory in Wales to a subsidiary of China's Wingtech Technology (600745.SS). It’s a sign of the growing wariness among western governments of the risks involved in Chinese investment. But Britain’s action looks muddled. The decision to force Netherlands-based Nexperia to sell most of its stake in the Newport Wafer Fab business isn’t illogical. The plant makes basic silicon wafers, used in chips for switches in domestic appliances such as vacuum cleaners. The UK government fears it could produce sophisticated compound wafers, which can…