Increasingly, the women’s march looks to sound the trumpet for a new surge in oppositional politics during the Trump era–however long it lasts.

Counter-inaugural protests are nothing new, but this effort is getting more and better attention than any others in memory. More than that, the prime target, Trump, is coming into office with a slighter reservoir of support than any president in at least a century.

Is the march going to change anything?

Not by itself, but as part of a much bigger process of organizing and staking out positions……..maybe.

Organizing the march started with a couple of stray social media posts on election night calling for an anti-Trump demonstration (See Julia Felsenthal’s Vogue article on the development). The organizers worked hard to avoid restating a familiar, but limited, white middle-class feminist take, bringing diverse organizers and organizations into the fold in early stages of planning. Early reports emphasized diversity and inclusion, but avoided a clear set of demands or issues. The familiar risk here was to use the extraordinarily diverse opposition Trump has provoked to put together a broad coalition that offered little more than general distaste.

There’s a trade-off between the breadth of an event coalition and its clarity and vigor. The foggier the issues, the more people and groups who might turn up….once. Tighter and clearer politics make for better sustained engagement, but expanding is tougher.  Organizers for any cause have to negotiate a tricky balance, walking a tightrope over the perils of vacuousness on one side and marginalization on the other.

But a platform appeared a few days ago, and although it’s extensive, it’s certainly not a tepid reach toward a mushy consensus. The guiding vision, that women’s rights are human rights and human rights are central, emphasizes not just equal opportunities, but protections of reproductive rights, sexual minorities, civil rights, labor, and the environment.  The list of participating organizations is very long, anchored by Planned Parenthood and the Natural Resources Defense Council, but it’s not unlimited. The spat about deleting New Wave Feminists, self-described as “badass prolife feminists.” demonstrated a willingness to take tough stances and risk enemies that is essential for building an effective campaign.

Although the first reports on Saturday are sure to focus on the size and tenor of the event (how many people? how disruptive?), more important are the organizations and commitments that come out of it.

Evaluations of an event like this virtually always overemphasize the event itself, and look for instant responses that are rarely in evidence. A president Trump is unlikely to change his policies or tone in response, and elected officials who already support him are unlikely to defect dramatically.

But a successful campaign works over time. The women’s march will effect influence if:

Activists, analysts, reporters, and politicians feel compelled to pay attention to the issues the demonstrators raise;

people who attend get a sense of political possibilities and their own potential power;

activists return to their communities, sporting tee shirts and pussyhats, proudly claim their participation and work to find ways to continue their efforts at home;

protesters connect with people and issues they didn’t previously know, and forge new alliances;

organizations build contact lists and active memberships–as well as alliances;

allies in government are encouraged to take a tougher opposition line;

opponents in government find excuses to distance themselves from the new administration and its policies–and political advantage in doing so;

supportive spectators get a sense that they’re not alone.

If the women’s march makes for a spectacular display without follow-up or ongoing engagement, it won’t count for much. But if it’s the effective call to action that organizers envision, all kinds of things become possible.

It’s not the moment, but the momentum that matters.