If the tone of Johnson’s writing on the blog sometimes bordered, as his detractors claimed, on hate speech, that of his mostly anonymous commenters was reliably worse. A popular blog like L.G.F. functions as a kind of cloud-sourced id. It is not uncommon for a simple, 200-word post to accrue upward of a thousand written responses from readers. The question of how responsible he is, or should be, for these expressions of uncensored reader sentiment is one that Johnson, like many bloggers, has struggled with; but in the middle years of the last decade, whether for free-speech reasons or simply because he enjoyed being the popular focal point of such strong nationalist feeling, he did very little to rein it in. Muslims were described as “vermin.” The posthumous nickname St. Pancake was coined for the young American pro-Palestinian activist Rachel Corrie, in reference to the Israeli bulldozer that killed her. Discussion of U.S. foreign-policy options included terms like “targeted genocide.” As for Palestinians, “they don’t need statehood,” offered one commenter; “they need sterilization.” And on and on. A so-called stalker blog, called L.G.F. Watch, sprang up to document instances of what it considered hate speech on the part of Johnson and his followers. Vanity Fair’s James Wolcott compared Johnson’s site to a “disorganized Nuremberg Rally.”

But enemies themselves are a kind of currency on the Internet, and for every attack L.G.F. provoked as a place that permitted and even fostered bigotry against Muslims in particular, new allies rose up to link themselves to Johnson and his causes. Those links were both spiritual and literal; allowing (or preventing) less-successful sites to post a link to yours, and maybe offering them a link on your own site in return, turns you into a kind of taste maker, a locus of tangible power. L.G.F. was, by 2007 or so, at the heart of a vast, amorphous grid of right-wing sites of every description, an interdependence that Johnson himself had become, in a way, too popular to control.

That concept of the link, in all its permutations, is the key to what happened next, both to Johnson and because of him, and it says something enlightening not just about blogging but also about the nature and prospects of citizen journalism. Whatever you think of him, Johnson is a smart man, a gifted synthesizer of information gathered by other people. But just as for anyone in his position, there is an inevitable limit to what he can learn about places, people, political organizations, etc., without actually encountering them. Instead of causes and effects, motivations and consequences, observation and behavior, his means of intellectual synthesis is, instead, the link: the indiscriminate connection established via search engine.

IN OCTOBER 2007, Johnson was asked to take part in what was billed as a Counter-Jihad Conference in Brussels, a gathering of fewer than a hundred politicians and opinion leaders from around the world who convened to share ideas and strategies for combating the spread of militant Islam. Johnson was not the only writer invited — Geller was there, as well as Robert Spencer of jihadwatch.org (a Web site Johnson himself designed), to name two — but he did not go. “I’m just not a joiner of these things,” he says.

The conference finished up in Brussels, and “the next day,” Johnson remembers, “people were e-mailing me saying, ‘You might want to cover this.’ So I started looking into it.” He discovered that among the conference’s 90 or so participants — though not among the speakers — was a man named Filip Dewinter, a leader of a Belgian-nationalist political party called Vlaams Belang, or “Flemish Interest.” Vlaams Belang, which has a history that reaches back to the wrong side of World War II, has an unabashed record of inflammatory rhetoric and hateful, opportunistic verbal viciousness of all sorts; a few years ago, for example, the party announced an advertising campaign in Moroccan newspapers and magazines to “discourage foreigners from coming to our country.” And as recently as 2004, it was condemned by the Belgian Supreme Court for incitement to discrimination and racial segregation. (The party responded by changing its name.) Even to most right-wing sensibilities, Vlaams Belang is certainly beyond the pale. Still, whether or not Dewinter, who has said that “in Flanders, the multicultural society has led to a multicriminal society,” is more extreme than the commenters who appeared regularly on Little Green Footballs seems like a subject on which right-wing minds might reasonably disagree. Perhaps that still happens somewhere. Gray, however, is not a popular shade on the Internet.

It seems borderline ridiculous that the political character of an extremist Belgian party, which in the last parliamentary election captured just 17 seats out of 150 in the Chamber of Representatives, should become the issue over which a kind of civil war among American conservatives broke out, but that is what happened. Opposing “Islamofascism,” Johnson had come to believe, shouldn’t require identification with fascism of the older sort. Johnson began taking shots at not only Vlaams Belang, an organization it seems safe to say the vast majority of his readers had never heard of, but also at formerly favored colleagues like Spencer and Geller, to whom, by attending the same conference, the European neofascist movement was now . . . linked. Johnson first hinted, and eventually demanded, that they publicly distance themselves from both Vlaams Belang and the conference itself, and when they demurred, he publicly distanced himself from them.

“Filip Dewinter has said some things I deplore,” Spencer says. “But I don’t consider myself responsible for him just because I was at this conference and he was, too. That’s an outrageous kind of guilt by association. Let me ask you this: a few years ago I spoke at a Yom Kippur service, and one of the other speakers was Hillary Clinton. Does that make me a supporter or her work, or her of mine?”