Sen. Roger Wicker, the high-profile Armed Services Committee chair, has proven a reliable ally to President Donald Trump by shepherding through his most controversial Defense Department choices and unabashedly praising many of his decisions. But even as he provides support, Wicker is quietly emerging as the Pentagon’s unlikely foil.

The senator from Alaska, who has become known for breaking with her party in the Senate, said the threat of political retribution for crossing Trump is “real.”