On June 1, 1950, Margaret Chase Smith — a first-term Republican senator from Maine — rose on the Senate floor and delivered her "Declaration of Conscience": a direct rebuke of Senator Joseph McCarthy's smear campaign, delivered while he sat rows away, at a moment when nearly everyone in her party judged it safer to stay quiet.
She did not name McCarthy. She didn't have to. "I don't want to see the Republican Party ride to political victory on the Four Horsemen of Calumny — fear, ignorance, bigotry, and smear," she told the chamber, adding that the right to hold unpopular beliefs shouldn't cost Americans their reputations or livelihoods.
Six other Republican senators co-signed. McCarthy dismissed them as "Snow White and the Six Dwarfs," and Smith paid the expected price in committee assignments and party standing. Four years later the Senate formally censured McCarthy, and Smith's speech entered the small canon of moments when a legislator chose the country's political health over the party's short-term advantage.
That's the bar for this wall: a documented act, against self-interest, that defended the norms everyone depends on. They exist in both parties, in every era. When we find one, it goes here.