Editor’s Note: Guest columnist Edward Alden is filling in for Kimberly Ann Elliott, who will return next week.

The latest opinion polls in the United States show former Vice President Joe Biden with what looks like a commanding lead over a COVID-stricken President Donald Trump, less than a month away from the presidential election on Nov. 3. If Biden can sustain that lead and win a decisive victory, the country would avoid the damage of a long and contested ballot count that would leave America even more internally divided. For much of the rest of the world, it would rekindle the hope that the U.S. might start looking something like its former self again. But that hope rests very much on an unknown: Was Trump a shocking aberration from an open, engaged and responsible America, or does he represent a more lasting set of impulses that will not disappear when he is off the stage? ...