Tucker Carlson was talking to U.S.-based Kremlin intermediaries about setting up an interview with Vladimir Putin shortly before the Fox News host accused the National Security Agency of spying on him, sources familiar with the conversations tell Axios. Why it matters: Those sources said U.S. government officials learned about Carlson's efforts to secure the Putin interview. Carlson learned that the government was aware of his outreach — and that's the basis of his extraordinary accusation, followed by a rare public denial by the NSA that he had been targeted... The first — and least likely — scenario is that the U.S. government submitted a request to the Foreign Intelligence Surveillance Court to monitor Carlson to protect national security. A more plausible scenario is that one of the people Carlson was talking to as an intermediary to help him get the Putin interview was under surveillance as a foreign agent.