If you are a Clinton Democrat—which based on that polling is a redundancy—it’s hard to see how a tough competitor who might weaken your candidate would be a welcome thing. But without a get-in-shape primary, would Clinton be ready for the close punches of the general election? Her book tour suggests she’s rusty. A Democratic coronation would start the general election attacks early, without the benefit of a clear GOP opponent she could counterattack.

A primary fight would force Clinton to draw clear lines about what she believes, why she’s running, and why her message is something more than “It’s my turn.” These are all things smart Democratic strategists say she needs to do. The Democratic primary race would be covered by a fevered media obsessing over a battle between two female candidates, which would mean Clinton’s sharpened message would be broadcast to the general election audience, helping her in the fall.

Warren would help Clinton put her best foot forward in another way. Warren has never run anything. Clinton would exploit her opponent’s lack of experience by discussing her relatively vast résumé. That would lead to a conversation about presidential qualities, a worthy conversation some of our best Americans have been trying to promote for years. How important is it to have the temperament, experience, and toughness that come from being in the Washington battle for so many years? What are the downsides of Hillary Clinton’s veteran status?