Mr. Perry’s mistake was not a big deal, practically. If elected, people with briefing books could remind him of the third department. It was a big deal politically because of an existing perception, which his opponents had seized on, that he was too dim for the presidency. On national TV his bulb flickered, and it was lights out.
Likewise, Mr. Biden’s verbal disaster, as he insisted for weeks after, did not undo any accomplishment of his, nor any of his opponent’s offenses. But it manifested in living video the concern among the public (shown in polling) and in his party (whispered in private) that he had lost too many steps with age.
After that night, every appearance he made, every conversation about him, was framed by the memory of him exposed under the stage lights wearing the gaping mask of mortality. You could even say, and some did, that the debate did not simply reinforce an impression of mental decline but starkly exposed the thing itself.
People can argue whether Mr. Biden’s downfall shows the value of TV debates or proves them a curse. However imperfectly, these productions give voters information. This one is forcing the Democratic Party to make a change that its voters might have demanded had they seen the same thing months ago.
Then again, TV politicking simply selects for politicians who are good at TV — charismatic-cool like Mr. Obama, provocative-hot like Mr. Trump — and being telegenic does not necessarily mean having good policy or judgment or decision-making instincts.
But it is a false dichotomy to claim that there is TV, an artificial arena for fake performance, and then there is the real world, where a president does important business. TV is part of the real world. It is where presidents inspire, console, advocate, persuade, create an identity, make connections, seize attention, build support — and, yes, win elections, without which they can achieve nothing at all.
We may be better off for that or worse. But try to argue against what people have seen with their own eyeballs, as Mr. Biden discovered, and you will lose that debate too.
