In the beginning, his defenses of the Central Library Plan seemed methodical, as if motivated more by loyalty to his new bosses, the library’s trustees, than by his own convictions. Of course, his dutiful stance may have owed something to the fact that, in November of 2011, Marx suffered the public embarrassment of being arrested in upper Manhattan for driving while intoxicated, after which he was clearly not going to do anything to ruffle feathers further. Even before that incident, however, his relationship to the trustees was complicated by the clear difference in style between him and LeClerc, who seemed to enjoy the social side of the president’s job a lot more than Marx did. Not long after his arrival, Marx suggested that the library’s major fund-raising dinner, called the Literary Lions and overseen for years by Gayfryd Steinberg, a longtime trustee and the wife of the financier Saul Steinberg, was rather more opulent than necessary. Elaborate and expensive decorations were not what the library was about, he said, and he called for a stripped-down Literary Lions dinner. This move made Marx no friends, and cost him a few of his allies among the trustees, at least until he quickly conceded that he had misread the spirit of the library’s donors. The dinner is once again being ramped up.

As Marx settled in and the embarrassment of the driving arrest receded (he lost his driver’s license for six months, and after his suspension ended he decided that he would forgo owning a car in the city), he seemed to take more ownership of the Central Library Plan. By last spring, when he decided to appear at a public forum about the plan at the New School and confront critics directly—the tenor of the forum was heated but civil—the C.L.P. was clearly Tony Marx’s baby.

The plan is now budgeted at $300 million, but Marx is unequivocal in his belief that going ahead with it is not just the only way in which the library can assure its financial security, but the best route toward the open, democratic institution he wants the library to be. “We are envisioning something that doesn’t exist anywhere else in the world,” he said to me. “We are combining a great research library and a huge circulating library. We want everyone from the unemployed to the Nobel laureate. If this building works, it will lead the schoolkids who come here to aspire to what the Nobel laureate is doing.” He asserts that closing the Mid-Manhattan Library and the Science, Industry and Business Library and incorporating them into the main library will save $15 million per year as well as allow the institution to recoup the value of those properties—money that, at least in theory, could go toward hiring more library staff and buying more books. Funding for both professional staff and acquisitions was cut back during LeClerc’s administration, contributing to the climate of mistrust that now surrounds the library’s relationship with writers and scholars.

Marx resents the notion that the renovation will compromise the library’s service to scholars. “We have a fundamental responsibility to preserve the great research collections and to assure the public access to them,” he said.

Marx makes a clear distinction between the complaints of writers and scholars such as Joan Scott and Stanley Katz—who was one of Marx’s advisers when he got his Ph.D. at Princeton—and the keep-the-riffraff-out argument Edmund Morris made in his op-ed. Marx established an advisory committee of writers and scholars and met with Scott and Katz. Robert Darnton, the library trustee who is also the director of the University Library at Harvard, wrote his own defense of the library plan in The New York Review of Books, and while he took pains to say that he was writing not as a trustee but “only in my capacity as a private individual,” his essay was nevertheless as close to an official response to the piece in The Nation as there was going to be. Off-site storage is a fact of life in the 21st century, along with digitization, Darnton wrote, and he argued that they did not have to compromise the seriousness of the library’s mission. “What I care about more than anything else is the democratization of knowledge, and libraries, far from being obsolete, are at the center of all of this,” Darnton said to me, sitting in the 18th-century house in Harvard Yard that serves as his office.