Over the course of forty-plus years of neoliberal offensive, revolutionary socialists in groups like the International Socialist Organization, of which I was a member until its recent dissolution, performed the valuable service of helping keep Marxist ideas alive by insisting that class struggle would eventually revive, that the Left should not limit its prospects solely to the confines of the Democratic Party, and that capitalism itself would soon enough force socialism and revolution back onto the popular agenda.

Sam Farber’s contribution, “What Revolutionary Socialism Means to Me,” confirms the value of sticking up for these points. And Farber has consistently done so over the years in a creative and nondogmatic manner. Hailing from the same broad political family, I agree that our tradition can help “provide some guidelines” to today’s new socialist movement and reinvigorated class struggle.

But revolutionary socialists must go a step further. We must identify where our fealty to very decent starting propositions over many reactionary decades may have dulled our sensitivity to new developments we didn’t expect.

Last year I wrote that “democratic socialism and revolutionary socialism share a great deal — and where we differ, we will debate our ideas and test them in practice.” But the reality is that the proponents of democratic socialism have grown proportionally stronger over the last few years because they have answered some key questions correctly; revolutionary socialists, meanwhile, have hesitated. My specific criticism of Farber’s piece is really a criticism of my own mindset, and it pertains to the problem of how to use knowledge of the past in order to make it useful today.

It’s certainly useful to know history that can warn a movement of potential pitfalls. For instance, Farber is exactly right to stress that “what distinguishes the politics of revolutionary socialism in terms of their participation in today’s struggles is its refusal to compromise the organizational and political independence not only of working-class organizations, but more generally of the social movements of the oppressed.”

But how do we do that? Farber stops short of giving the sort of concrete answers that democratic socialists have delivered in order to grow and spread their influence for the benefit of the whole movement. Revolutionary socialists have too often missed the forest for the trees. Here are two examples.

First, Farber reviews the UAW’s capitulation to Chrysler in 1979 and then warns that Jeremy Corbyn’s proposal for an “inclusive ownership fund” providing corporate shares for workers might dull class antagonism. He then suggests this will be “emulated by Bernie’s Sanders’s coming proposals.” Were either Corbyn or Sanders’s plans to come about without first throwing into the air major aspects of the assumed neoliberal order, Farber would be right to suggest that “in political and social-psychological terms, this proposal would also significantly increase the workers’ identification with ‘their’ company.”

Certainly, it is fair to criticize specific proposals put forward by Corbyn and Sanders on any number of grounds. But is the main impetus of Sanders’s campaign to bind workers to their companies more tightly? Quite the opposite: Sanders’s main thrust is to encourage teachers and other workers to strike.

So the concrete question is, if Sanders’s campaign can help build the socialist movement, should we (however critically) support him? Yes or no?

Second, Farber warns that the “newly minted socialist officeholder will find common ground with decent legislators and government functionaries” and then be caught in the web of co-optation. He is absolutely right to point to this potential. One only has to utter the name Alexis Tsipras to know that seemingly radical politicians can become capitalist enforcers.

But does knowing that Cyril Ramaphosa went from union leader to billionaire, or that the European left has hit an impasse, or that the Lenin-Kautsky debate deserves serious study answer the question of whether or not to vote for Sanders? Or whether or not to support Alexandria Ocasio-Cortez and Rashida Tlaib?

In 2016, I believed that Sanders would be brought to heal by the DNC. Instead, he helped fuel the growth of the Democratic Socialists of America and, remarkably, played a role in giving teachers and others the confidence to strike. And recently AOC tweeted in support of one of the first political strikes in modern US history at Wayfair in solidarity with immigrant families caged in concentration camps.

Does this mean that Farber’s warning about the potential pitfalls of running socialists on the Democratic Party ballot line is irrelevant? Not at all. In fact, at some point, Farber’s call for explicit timelines and guarantees about building a new party will come into play.

And, if in five or ten years from now, we still have not breached this wall, all the dangers that Farber points to may be proven correct. After all, it is one thing for a movement to occupy a few dissident seats in Congress and another to be able to exert some influence (“discipline,” we might say) over hundreds of elected officials all across the country in preparation for launching a “mass party of the working class with a socialist program.”

AOC, Bernie, Chicago’s recently elected six socialist city council members, Rep. Rashida Tlaib, and others are at this point confounding the revolutionary socialist expectation that they will fall prey to what Karl Marx referred to as “parliamentary cretinism” in short order.

Farber is right to champion Rosa Luxemburg’s insight that humanity faces a choice between socialism and barbarism, even in advanced democracies. And this choice “poses the possibility that revolution may occur not as the crowning advance of the forces of progress, as welcome as these might have been, but rather as a defensive last gasp and decisive fight against brutal regression.”

Yet timing and preparedness in politics is everything. History does not repeat itself, but the socialist movement of which Marx was a part needed several generations to mature. If our socialist movement is not prepared to fight on multiple fronts using a variety of tactics over the coming decades, we will be weaker for it. Engels wrote in 1891, “for the time being it is not we who are being destroyed by legality. It is working so well for us that we would be mad to spurn it as long as the situation lasts. . . . . [but] a war would change all that. And war is liable to break out at any moment.”

That seems about right to me. Take all the ground that is open to us for as long as we are able, while keeping in mind that the state is hostile to the working class and will use force, the law, its political instruments, and all the means at its disposal to stop us in the short and medium term, while reserving the Pinochet option in the long run.

In this respect, Farber raises a legitimate criticism of Karl Kautsky, who placed so much emphasis on the first aspect of Engels’s formulations — elaborating a strategy so compelling that it earned him the honorific “the Pope of Marxism” in the years after Engels’s death in 1895 — that he was ill-prepared to respond effectively to the First World War. But that shortcoming should not blind us to what is valuable in Kautsky’s strategy for socialists today.

For decades, revolutionary socialists in the United States had few prospects and were forced to make the best of a bad situation. We did our best to work in labor or social movements where our radical politics could only be put into practice in small ways. We wrote and taught and did our best to pass on what we learned to a new generation. We built small organizations of hundreds that we knew would have to eventually combine with much more powerful forces. Our work was hemmed in and too often made a virtue out of necessity.

Farber is one of the most open-minded and non-sectarian revolutionary socialists I know. His insights and knowledge are a treasure trove for the new socialist movement, and he was rightly more attentive to the problems of translating the experience of revolutionary organizations from the era of the Russian Revolution to our own time. So Marx’s advice to socialists in 1868 to a situation analogous to that of our own today applies to many of us, myself included, much more so than him.

“The dissolution of the General Association of German Workers [a significant but small organization of working-class socialists] gave you the historic opportunity to accomplish a great step forward and to declare, to prove if necessary, that a new stage of development had now been reached, and that moment was ripe for the sectarian movement to merge into the class movement . . .  Where the true content of the sect was concerned it would, as with all previous working-class sects, be carried on into the general movement as an element which enriched it.”

Rather than revolutionary socialists and democratic socialists defining our “points of honor” that “distinguish” one from the other, it is time to merge the best of our ideas, many of which we share to begin with. Socialists from different traditions will find themselves agreeing and dividing over many of the battles to come, but I suspect that these confluences and arguments will not fall neatly along the theoretical or traditional lines developed in the period of defeat.

Hand to heart, who in 2015 would have expected Sanders to be joined by radicals in Congress like AOC, Ilhan Omar, and Pramila Jayapal to propose the abolition of $1.6 trillion in student debt? That is not only an economic demand, it is a political demand, if we can win it, as it would simultaneously weaken finance capital’s stranglehold on the Treasury Department and lift the fighting spirits of tens of millions of young workers.

Marxists are materialists. We do not base our prospects on what we wish to be true. With his typical bluntness, in the face of high Hitlerism and Stalinism in 1940, Trotsky wrote, “if the world proletariat should actually prove incapable of fulfilling the mission placed upon it by the course of development, nothing else would remain except only to recognize that the socialist program, based on the internal contradictions of capitalist society, ended in Utopia.”

Of course, he rejected that thesis in the months before his assassination, but the power of neoliberalism to remake the world in its image has tested its limits. In the last few years, hundreds of thousands of striking teachers have revived hope that the working class’s “mission” is not a utopia. And millions more, great layers of the two youngest generations, are gravitating towards socialist ideas inherited from the past and redefining socialism for themselves for the future. A new political leadership is arising on both the picket lines and at the ballot boxes and those leaders are picking fights that will be difficult to contain within the bounds of congressional decorum.

I agree with Farber, and many other socialists, that it was a mistake for AOC to endorse Gov. Andrew Cuomo given his “two-term record reveals a critical lack of support for healthcare for all New Yorkers, or ambitious climate and jobs programs, or protection for immigrants from deportation.” Socialists of all stripes should make their opinions known about such decisions, for instance, should he not win, Sanders will in all likelihood support the Democratic nominee in 2020, and he insists socialists should remake the Democratic Party, a utopia if there ever was one. But it will be the sum total of decisions like this over the next five or ten years that will determine the trajectory of the socialist movement. Socialists from revolutionary and democratic traditions must judge the directionality, the timing, and the ethos of the movement, not simply assess individual data points.

As Keeanga-Yamahtta Taylor wrote last week, “Sanders is a reflection of the deepening radicalization in this country, but he is also helping fuel it forward by naming the source of misery and rejecting the well-worn habits of blaming American workers for their own despair.” The same can be said of AOC’s inspection of immigrant concentration camps in Texas. She is not only reflecting a mass outcry and the rumblings of mass action — she is fueling it, not only rhetorically, but physically by putting her body on the line.

Engels died in 1895 as a critical, but enthusiastic, friend of the German Social Democratic Party (SPD). With all the limitations of exile, he embedded himself in that movement and fought to strengthen it by mobilizing his previous decades of experience and knowledge. Twenty years later, the leftist, anti-war wing of the party proved too weak to overcome its leading bureaucracy, and they lined up behind their rulers in the Great War.

That trajectory was not inevitable. It was determined by 1,001 fights within the SPD over decades, by real people, by social forces, and not a little luck. Our movement’s fate will be settled by the same means, and it will be messy. If we want to play a role in achieving a different outcome, revolutionary socialists will have to prove we are able to merge with the movement of the present. The power of political ideas is not only measured by their logic, but just as much by their social and psychological proximity to the social and class struggles a new generation of fighters adopts as their own.