A Clear Choice on the Issue Voters Care About Most

The most important distinction between the two candidates for the White House is that Vice President Kamala Harris is committed to democracy and the rule of law and Donald Trump is not. It’s a race that is, fundamentally, about who has the right temperament and is fit to be the next president, and the answer is not in question.

Consider, for instance, Liz Cheney’s endorsement last week of Ms. Harris. Ms. Cheney, a former Republican congresswoman, supports the vice president even though she disagrees with many, perhaps most, of Ms....