Why did John Ratcliffe go to Moscow?

Thomas Wright/The Atlantic: On his way to Moscow, Ratcliffe stopped in Latvia. Today, the Latvian prime minister called the trip a “very good signal,” which seemed to imply that Ratcliffe had been there seeking to bolster European security. If the CIA director carried a warning with him, it should have been an unambiguous one: Any attack on NATO territory would bring in the United States. Trump might not want to make that type of commitment, but it may be necessary to ensure that Putin never concludes that he has an opportunity to start a war that breaks NATO…