Biden can and should claim an election mandate. By the time every vote was counted close to 83 million people had voted for him in what turned into an impressive victory over Trump. While the Republicans will contest this claim, most House and Senate Democrats, not to mention most Biden voters, believe that Biden earned a mandate to govern. Much of the broader democratic coalition will be of like mind and disposed to support his agenda, which includes addressing the health and economic crises stemming from the coronavirus and support for popular measures such as a $15 minimum wage, paid sick leave, a public option for health insurance, criminal justice reform, and a massive investment in green infrastructure.

The left, if it is smart, won’t be dismissive of Biden’s mandate and act as if it won the election, and thus in the driver’s seat going forward. But my fear is that some will and as the election becomes yesterday’s news, its support of Biden-Harris and their agenda will turn into righteous opposition. In other words, if the accent in the run up to the election run-up was on cooperation and unity in these circles, the accent in its aftermath will be on conflict and intra-party struggle, thinking that the imperative of unity – and left center unity in particular – no longer holds. But there is little evidence at present or in the historical record in the 20th century to sustain such a view.

In the 1930s, the Communist Party pushed the needle to the left on one issue after another, but it also came to understand as the decade wore on that the enactment of meaningful reforms in the midst of a deep depression wasn’t the handiwork of the left alone. To the contrary, it was the result of the accumulated actions of political and social constituencies, organizations, and parties of varying political orientations. At the head of this coalition at that time wasn’t Earl Browder and the Communist Party, but FDR and New Deal Democrats.

The party, in short, came to learn (and this is to its credit) that only an expansive coalition of diverse forces, albeit with a special emphasis on the industrial working class, Black-white unity, and flexible tactics stood a chance of making the transformative changes that were necessary at the time. Did it always get it right? No. But it got more right than wrong strategically and tactically and as a consequence, the party emerged as a significant force in U.S. politics at the time.

Not since then has the left had such an outsized role in shaping the country’s direction. That could change in current circumstances, but only if the left is able to combine the dialectics of unity and struggle, only it lifts up the necessity of left center unity.