The first, which Ed Kilgore, a Democratic strategist and New York magazine columnist, has emphasized, is that it would help unify Democrats going into the fall. To be sure, the mere presence of Trump on the ballot is already serving as a powerful centripetal force. But the fact remains that the Democratic Party today is a fractious coalition, and much of its progressive wing, which plays a key role in mobilizing support at the local level, has little enthusiasm for Biden. In an interview with Politico on Wednesday, Representative Alexandria Ocasio-Cortez, who supported Sanders during the primary, called on Biden to choose a more progressive running mate who “he knows may push him.” Picking Warren would address this issue, and it would also send a powerful message to the broader American public that, in trying to save the country from Trump, Democrats are willing to overcome their internal rivalries. “Biden-Warren would be an emergency-leadership ticket for perilous times,” Kilgore noted.

It would also elevate a female politician—Biden said last month that he intends to pick a woman—who, during the Democratic primary debates, was consistently the most impressive performer. From early on in the process, Warren’s extensive platform, together with her obvious command of the issues, enabled her largely to dictate the terms of the policy discussion. But she also displayed her toughness and killer instinct. Who could forget the debate in Nevada, on February 20th, when she eviscerated Mike Bloomberg? Warren “would be an effective ‘attack dog’ if needed in the fall,” Mark Green, the veteran New York progressive, pointed out in a Nation article, in which he also argued that Warren had the temperament and experience to “help Biden win and govern.”

Certainly, Warren would be more than able to handle Mike Pence in a Vice-Presidential debate. But Biden could also use her help as he addresses a more immediate challenge that is dominating the news: the policy response to the coronavirus crisis, including the large-scale corporate bailouts that Trump is rolling out.