An inability to focus on consequences that do not center on him. Check. An absence of empathy for others. Check. A lack of impulse control coupled to a need to lash out at perceived offenses (and offenders). Check. A vainglorious view of himself. Check. An ever-present, almost childlike, need for praise. Check.

President-Elect Donald is a narcissist. That’s the conclusion of Alan J. Lipman, a clinical psychologist, chronicled in a commentary on CNN. But we already know that, don’t we? We’ve seen it repeatedly at his rallies and in his Twitter rants. But so far, he’s insulated himself from the consequences of his narcissism. Even past Republican critics, such as the speaker of the House, and big-money donors who did not support his candidacy are falling in line, creating an imaginary unity.

President-Elect Donald’s egregious behaviors have become acceptable because so many legislators and donors have too much at stake (power, influence, government contracts, etc.) to suggest the emperor-elect is naked.

But there’s one judge of presidential behavior, character, and leadership President-Elect Donald has yet to face — George Gallup’s question:

Do you approve or disapprove of the way ____ is handling his job as president?

Beginning at noon on January 20, President Donald will face that poll question. Each day. Day after day. How will he and his aberrant Twitter account react to the repeated judgments of a rolling panel of 1,500 anonymous respondents?

Gallup first asked that question about Franklin Delano Roosevelt in the 1930s. His organization has continued asking it since. Nowadays polling organizations do daily tracking polls of perception of presidential job performance. Politicians, especially presidents, keep close track of such polls (despite, when poll numbers are low, the occasional dark muttering that “polls don’t mean anything”).

A year ago, the Pew Research Center looked at presidential job approval ratings (both its and Gallup’s) back to Eisenhower. It noted several findings. Among them:

• Views of the opposing party have become increasingly negative. No surprise there. Antipathy for the other party deepened during the Reagan era. Thank Reagan image maker Michael Deaver for accelerating it, and House Speak Newt Gingrich for amplifying it. Lest we forget, Lee Atwater, as a Reaganite and Bush No. 1 campaign manager, divided the parties further.

• Scandals don’t necessarily precipitate a sudden drop in approval. Clinton hit 71 percent while mired in the Monica scandal and hit 71 percent again when impeached. Reagan dropped to 49 percent amid the Iran-Contra scandal but left office at 63 percent. Nixon, hammered by Watergate, fell from 68 percent after re-election to 24 percent.

The “Access Hollywood” video depicting Candidate Donald as a misogynistic dimwit didn’t keep him from being elected. So presidential displays of rampant sexism and arrogant racism by him or members of his advised and confirmed administration are unlikely to crank up or down his job approval rating.

But what about promises made but broken? Ask Bush No. 1 about that. “Read my lips: No new taxes” did not lead to a second term. Politifact has listed President-Elect Donald’s top 10 promises, beginning with building The Wall and sending The Bill to Mexico. But politicians are always vague, right?

“Voters generally do not punish candidates for being vague, and in partisan elections voters actually prefer ambiguous candidates over precise ones,” Stanford University political scientists Michael Tomz and Robert Van Houweling found in a study. “The reason, we find, is that ambiguity allows voters to ‘see what they want to see’ in members of their own party.”

Presidential candidates are always damnably vague. But presidents are judged on actual performance by the rolling panel of 1,500 poll respondents. As it becomes apparent to the 62,979,879 citizens who voted for President-Elect Donald that what he says and what he does differ, will they ignore his tweeted deflections from the facts? When asked how President Donald is doing, will they begin to rank him lower?

Presidential approval ratings rise and fall over a term (or two) as seen in this Gallup chart. They can be influenced by how Americans perceive their financial well-being (“It’s the economy, stupid”), unexpected or tragic events (September 11, 2001), or the perception of too much corruption (Watergate).

That’s why late last year I suggested Americans ask themselves the Reagan question midway through President Donald’s term. Their answers will likely determine his job approval rating, and whether he’ll be around for a second term.