Readers of a certain age will remember Margaret Chase Smith (1897-1995), the Republican senator from Maine who enjoyed a certain renown in her day as the first woman whose name was entered into the nomination process for president by a major party (1964), and for her daily habit of wearing a fresh rose in the buttonhole of her business suit. Senator Smith had another distinction: She was an early Republican critic of Joseph McCarthy, and in June 1950 issued a “Declaration of Conscience” against his growing influence on the Senate floor.

For this she was reviled as “Moscow Maggie” by McCarthy’s staff. But as might be expected, it also earned her considerable admiration in the press, and among her Democratic colleagues in the Senate. She was known thereafter as the Conscience of the Senate—and often referred to as such, in public, without irony.