No greater act of press criticism exists than to launch your own publication. Starting anew allows a journalist to leave the cracked glass, dents and rust of the old behind, to reject the past and all its mistakes and compromises, and to show by example how the work should be done. To command a blank slate into existence and drop your pen on to it makes a critical statement like no other.

If I’m right about all of this, then Ezra “Wonkblog” Klein deserves acclamation as the press critic of the day, the week, and maybe even the month for leaving the Washington Post and joining with the blog consortium Vox Media (The Verge, SB Nation, Eater, Curbed, et al.) to start his own Web publication. In a Sunday evening post announcing the deal, Klein promised in a glancing blow at the Post — which rejected his creative vision — that his as-yet-unnamed site would jettison the “workflow built around the old medium” of print to re-imagine “the way we explain the news.”

No news consumer — even his fellow press critics — can wish Klein and his team anything but well. But the future is a dangerous place where past results do not reliably predict performance. Klein’s Wonkblog mélange of charts, policy explainers, economics reporting, and political opinion earned him the sort of canonization at a young age previously enjoyed by fellow liberal journalists Walter Lippmann, Joseph Alsop, and Michael Kinsley, as Matt Welch wrote in the Columbia Journalism Review. Klein’s audience grew and grew, Wonkblog became its own sort of publication tucked inside the Washington Post, and he disseminated his wisdom on new venues, including The New Yorker, Bloomberg View, and MSNBC.

Extending that success outside the sheltering wing of the Post will depend, of course, on Klein’s plans and Vox’s financial and managerial support. Rather than speculate on the scope and focus of Klein’s venture, I’ll speculate instead on the impediments that may inhibit his further rise, no matter what blueprint he chooses. As cutthroat and competitive as the modern newspaper business is, it has never been as cutthroat and competitive as the Web trade, a competition that will only grow fiercer. Obviously, newspapers have always poached the staffs of other newspapers and invaded the circulation territories of other newspapers. On rare occasions, they’ve been known to start competing titles. But the costs of entering the newspaper business — to acquire a press, a delivery fleet, a sales force, a product worth selling, and a product news consumers are eager to subscribe to — have been almost prohibitive for more than a half-century. In Warren Buffett’s parlance, dominant newspapers could mint money from inside the protection of their “moat,” the moat in this case being the high costs of entry into the newspaper business.

The newspaper moat suffered damage when commercial radio got started in the 1920s, again when television arrived in the post-war era, and took another hit when cable came on the scene in the 1970s. As early as 1992, years before the commercial Internet established itself, Buffett regarded the moat as too weak to fend off competition and ruled out buying additional big dailies. (He has, however, recently purchased a slew of smaller papers, acquisitions that I discussed in 2012.) The Web, as we all know, has so breached the newspaper moat that nearly every newspaper has established a parallel incarnation on the Web to fight back, with limited-to-no financial success. TV and radio have been similarly moated by the Federal Communications Commission’s reluctance to issue new TV and radio licenses in abundance. Likewise, members of the highly regulated cable industry, most of whom double as cable TV channel owners, have protected their moats by suppressing the addition of new, competing cable channels (unless they get a piece of the channel or some other remuneration).