Boy, whenever I see a link to the Atlantic my defenses go up Ken. Pretty interesting walk thru the history of the progressive party and political groups mounting pressures on FDR, etc... I take issue with the authors framing of 'leftism' as eventual chaos. Also could take issue with the 'backlash' of bold progressive legislation. I never saw these counterforces coming from popular opinion but rather from a top down assault by the entrenched economic interests from 1676 to the present day. I do think Beinart is correct about the ideas mainly coming from the left that have any broad popular support. I don't think his 'INCOMING!' anxieties about republican reaction is fully accurate. I subscribe to the 'convergence theory'- that by and by more people will find agreement on the system being jacked up and working against their interests than what the reasons are. But you godda have ideas to meet the problems.
To that end, Sanders has released a 10 point plan that he believes the democratic party should adopt and run on. It very much reminds me of a similar plan taken by Labor in the run up to the snap elections in the U.K. It ran in the washington post as an Op Ed peice on thanksgiving. Sanders go big or go home challenge