A group of former defense and intelligence officials and policy experts sent a letter on Thursday to Congress calling for an investigation into the Pentagon's decision to designate Anthropic a supply chain risk. The bipartisan coalition of 30 people said in the letter, shared with CNBC, that the purpose of deeming an entity a supply chain risk is "to protect the United States from infiltration by foreign adversaries." The group characterized Defense Secretary Pete Hegseth 's decision last