During his confirmation, both in public and in private conversations, Mr. Blanche sidestepped questions over whether actions Mr. Trump ordered were right, saying only that Mr. Trump had the right to do them. Mr. Blanche shares Mr. Trump’s view that the landmark 2024 Supreme Court ruling that granted Mr. Trump sweeping immunity from prosecution represents a broader endorsement of expanded presidential authority. Mr. Barr quit two years later when pressured by Mr. Trump to help undermine confidence in the 2020 election. Mr. Blanche’s experience as Mr. Trump’s private lawyer was not a reason to oppose him, Mr. Barr told Mr. Cassidy — but an asset. But the episode underscored, in the view of critics, the lopsided power dynamic inherent in the partnership between Mr. Trump and Mr. Blanche.