Jan. 6, 2021, the day a mob of Donald Trump loyalists carried out an insurrection against the Capitol, is etched in the minds of Americans. No doubt historians will memorialize that terrible, ugly day as a nadir in American democracy, a moment of shame that indelibly scarred the nation. It won’t be remembered by historians as a day of “legitimate political discourse.” And yet, the Republican Party has set out to brand Jan. 6 as exactly that. The insurrectionists who stormed the Capitol with the aim of nullifying the free and fair election of an American president were simply exercising “legiti…