Republican National Committee Chairman Ronna McDaniel recently asked “why are we losing with women?” Mr. Trump has promoted women to the highest echelons of the White House. But elevating energetic and effective leaders like Kellyanne Conway, Hope Hicks and Sarah Huckabee Sanders has earned him scant credit.

It’s too late for Mr. Trump to revamp his political personality. But with the 2016 election in the past, Nikki Haley on the ticket could tamp down the antipathy for Mr. Trump that seems to afflict so many moderate and Republican-leaning women. President Trump needs the prospect of a Vice President Haley to help recapture the White House.