Covering yesterday’s massive demonstrations in New York, Matt Yglesias, Ezra Klein, and Jesse Taylor all worry, to different degrees, about what Ezra calls “the ideological incoherence of protests.” They all suggest that what contemporary protests lack is the unified vision of the civil rights and Vietnam eras.

I’ve commented on protest here before, in particular on the anti-war protests of spring 2003, and on the subject of counting crowd size. On the relevance of protest and some changes in it over time, I think that the first of those posts might still have some interesting material.

But, to think about this idea of the good old days of ideological coherence, I went to the tape—well, to the file cabinet in the corner of my office, really—where five years of 60s and early 70s protest data is stored, and I looked up the largest protests of the era, those most comparable to yesterday’s demonstration.

The single largest event of the period was a Washington, D.C., antiwar rally of November 15, 1969, attended by an estimated 250,000 people. A quick read of the coverage of that weekend—like yesterday’s march, it really was a series of events, not a single event—demonstrates that participants were there to take part for many reasons, although they all ended up under the anti-war banner: Students protested the draft; religious activists ranging from Catholic to Quaker participated; radical leftists were there, as were elderly women and parents with their children, as were small groups seeking violent confrontations; also present were African American organizers and advocates for the poor, protesting the war’s diversion of funds from domestic programs. This is still an oversimplified list of participants; it’s clear that while the war was the most tangible target of the protests, many grievances actually brought protesters out. Like this weekend’s march, officially organized by United for Peace and Justice, that series of events had a nominal set of organizers, but plenty of other groups also participated. In a sister protest across the country, where another 100,000 people demonstrated, Physicians for Social Responsibility and the Gay Liberation Front were among notable organizations represented.

Similarly, earlier that year close to 100,000 people participated in a late-April anti-war march in New York City, in which anti-war and anti-racist claims were mixed. On the same day in Chicago and San Fransisco, another ten thousand protesters in each city marched against the war, poverty, and racism.

So, a pretty cursory look at protest data suggests that what we think of today as a unified antiwar protest was actually highly heterogeneous, both in terms of who participates as well as why they participate. The answer to Jesse’s question, “What would have happened if Selma was joined by the Socialist Worker’s Party, or anti-globalization people (or their relative counterparts from the 60s)?” is that in many cases that’s just what happened.

What might this mean for making sense of yesterday’s march? A couple of suggestions. First, the concern over a diluted ideology resulting in a lack of efficacy may not be warranted—which is not to say that there may be plenty of other reasons to worry about efficacy—because, like civil rights and anti-war protests of past eras, yesterday’s march did have a target, boiled down in all of its forms to the policies of the Bush administration. Second, I think that Ezra’s absolutely right when he says that, regardless of activist makeup, media portrayal is still important, and negative coverage can still scatter some of a protest’s power. Too much focus on the differences among activists, the expressive use of protest, or the carnival atmosphere of some protest will play down the unifying reason for protesters to come together; but, I would argue that this is less a function of changes in protest than in changes in how news is made.