I’ve had some conversations lately, on Twitter and elsewhere, that have renewed in my mind an old complaint: that readers rarely pause to consider the limits — including plain old word limits — that journalists typically have to contend with. All journalists have to deal with scarcities of time and space, but it has always seemed to me that op-ed columnists have it particularly tough.

I cannot count the number of times over the years that I have listened to people complain that a particular newspaper or magazine column fails to do justice to the nuances and complexities of a given situation. To which I always reply, though usually just in my head: “Right, and that’s because they get eight hundred words.”

It is the very nature of the opinion column — as inevitable as the sun rising in the East — that it paint with a broad brush. Issues and positions have to be presented in general terms; there’s no other way to present them, unless you’re writing about a topic that’s so simple that it isn’t worth writing about at all. Anything worthy of debate demands to be treated in great depth and detail, and yet the op-ed columnist is denied those very options.

I have never been a regular op-ed columnist, but I’ve written quite a number of one-off columns over the years, for the Los Angeles Times, the Wall Street Journal, and other venues — and I have always hated it. Hated it. Trying to fit an adequate account of something I care about into 800 words was inevitably a Procrustean exercise — and more than once I was told, hours before the newspaper had to go to press, that I was going to lose 150 or 200 of those words and would have to do further cuts. Writing that way was so consistently frustrating that, several years ago, I vowed that I would never do it again.

Those experiences just give me increased respect for those brave souls who take on the op-ed task. You can’t do that without knowing that any one column you write will likely be so full of logical or evidentiary holes that a fleet of trucks could be driven through it. Commenters will rush to point out all the counter-examples you failed to consider and all the complexities you took no note of. And in some absolutist sense those commenters won’t be wrong — but the op-ed columnist doesn’t get to write absolutely. He or she is allowed 800 words at a time.

So why should anyone do it at all, given the miserable constraints? Two reasons, I think. First, in a given column you might be able to correct one common error, or suggest one useful line of argument — and in that way contribute to the improvement of public discourse, if only in a small way. And second, while you can’t make a fully valid argument about a Big Issue in 800 words, you can develop ideas in multiple columns: you can, over months and years, articulate a reasonably comprehensive and consistent view of the matters you’ve been charged with treating.

But you can only do this if you consistently remember how limited and limiting the genre is. If you don’t, you can end up like Paul Krugman, an obviously smart person who seems to have come to believe that the world’s economic problems are simple enough that he can solve one per column. His thinking has shrunk to fit his column. (Not that I have ever agreed very often with Krugman, but he’s gotten worse and worse over the years.)

I think the best op-ed columnist in America today is Ross Douthat, and much of his success stems from his understanding of what he can do in 800 words — and, more important, what he cannot. May Ross always be properly uncomfortable with the constraints of his medium. As for me: that just ain’t my bag.