Big technology companies are seeing signs that the publics worries about government spying are a threat to their future profits, analysts say. These concerns havent started to hit their bottom lines quite yet. But critical international growth, particularly for businesses selling cloud-based products, has become more challenging after the disclosures this summer about the National Security Agencys methods, which reportedly include obtaining data from big tech companies. Apple, Facebook, LinkedIn, Google, Microsoft, Twitter and Yahoo! joined together on Monday to ask the U.S. …