Both these purist approaches underestimate the complexities of politics, which stem from our fallen nature as human beings. Politics involves complex moral and empirical calculations, and people of good faith might come to different conclusions about which political party and candidate to support.
The United States has had incredibly flawed presidents before. Woodrow Wilson waged an all-out assault on constitutional norms and individual liberties, attacking checks and balances while imprisoning his political opponents. And yet plenty of decent people voted for Wilson and worked for him. As Robert Caro's books show in (at times, nauseating) detail, Lyndon Johnson indulged in corruption and vulgarity; he used his political power to make himself quite wealthy and treated his staffers in a repellent way. And yet plenty of decent people supported and worked for him, too. Moreover, these people did not lose all moral standing because of this support.
A similar point could be made in the opposite direction. The United States has had great presidents, too, and yet plenty of decent and honorable people opposed them. Even Abraham Lincoln got only 55 percent of the vote in the 1864 election. Are the 45 percent of Union voters who voted for George McClellan (Lincoln's Democratic opponent) really unredeemable deplorables?
Moreover, the heterogeneity of human experience suggests that flawed leaders can make good decisions and that noble leaders can make bad ones. This means that commentators might praise certain aspects of an administration while criticizing others. For instance, many conservatives object to Lyndon Johnson's personal corruption and find that many of his plans for the "Great Society" inflicted great damage on the fabric of the nation, but many of these same conservatives also agree with a number of his civil-rights efforts. Are conservatives supposed to attack civil-rights legislation because they view Johnson as otherwise grotesque? Do conservatives somehow compromise their principles by signalling support for legislation that they otherwise agree with? Likewise, Richard Nixon is the bugaboo of many progressive nightmares--but you rarely see progressives say the EPA shouldn't exist because Nixon created it.
Politicians leave complicated legacies, and part of a serious, empirically-informed politics is attending to those details. That might mean praising things in the record of a politician you otherwise oppose, or criticizing things in the record of a politician you otherwise support.
The legitimacy of disagreement is one of the cornerstones of republican politics, so, in order for politics to work over the long term, we need to sustain the norm that it is okay for individuals to disagree about whether to support a given politician. The mode of apocalyptic politics--"we face impending doom so the norms of civic disagreement need to be overthrown"--can be appealing; it carries a thrilling charge of urgency. But it is also corrosive when carried over time because it eats away at the necessary presumptions of republican life.
The opposite of inquisitorial politics might be more modest, but it's also healthier (in part because it is more modest). It means calling out bad arguments when you see them, supporting what you think is good, opposing what you think is bad, and not reducing all questions of principle to factional allegiance. It means resisting paranoia and preferring reasonable skepticism to the eddies of public hysteria. It means surrendering the tactics of excommunication and instead embracing those of empathy and charity.
With that...
Merry Christmas and happy holidays to all!