The first presidential debate between Vice President Kamala Harris and former president Donald Trump was a missed opportunity for both candidates and, as such, a disappointment for American voters.

Trump had three points he needed to land against Kamala Harris: that voters cannot trust her because she is constantly changing her policy positions without a satisfactory explanation; that she covered up President Joe Biden’s cognitive deficiencies from the American people and then participated in a political coup to take him out when it was politically convenient for her; and that she has had three and a half years to do the...