NEW YORK - Lawrence Wright is the author of the Pulitzer Prize-winning "The Looming Tower," an investigation of the rise of Al-Qaida and the events leading to the Sept. 11, 2001, terrorist attacks. He relied in part on internal State Department documents, the kind WikiLeaks has just released by the hundreds of thousands.

"That was really helpful. I'd hate not to have such inside glimpses," Wright says of the documents he obtained, including how the State Department dealt with the Taliban in Afghanistan. He sees the short-term advantage to WikiLeaks, but wonders if books such as his will become harder to write.

"I worry that there will be a backlash in terms of classification, so that more information that would be considered merely confidential will be termed top secret and kept from wider distribution, so that people on the ground who could put such knowledge to work, won't have access to it."

Historians and writers are intrigued and concerned over the latest disclosures by WikiLeaks, the self-styled whistle-blower organization founded by Julian Assange, who has embarrassed the U.S. government and foreign leaders with his online releases, and is wanted for questioning in a rape case. They welcome timely and unfiltered information about world affairs, but not the possibility that fewer government officials will have access to information or willing to put their thoughts in writings.

The secret communications show that the U.S. is still confounded about North Korea's nuclear military ambitions, that Iran is believed to have received advanced missiles capable of targeting Western Europe and that the State Department asked its diplomats to collect DNA samples and other personal information about foreign leaders.

In Washington, the State Department severed its computer files from the government's classified network, officials said. By temporarily pulling the plug, the U.S. significantly reduced the number of government employees who can read important diplomatic messages.

James Mann, whose books include "About Face: A History of America's Curious Relationship With China," said it was up to historians to place the WikiLeaks documents in context.

"The memos tell stories, sometimes very interesting ones, but they don't tell the whole story. And yes, it will also lead to a backlash -- to some extent a backlash against putting information into State Department cables, but more generally a backlash tightening up the fairly extensive distribution of these cables within the US government," said Mann, who believes WikiLeaks would have affected his book on China.

"I would have certainly looked at the kinds of materials coming from WikiLeaks. On the other hand, the book would have been harmed if officials were afraid to put things into writing."

The WikiLeaks documents have been compared to the Pentagon Papers, an internal government study of U.S. involvement in Vietnam that was completed in 1967. The documents were leaked in 1971 by former Defence Department aide Daniel Ellsberg and included many damaging revelations, including a memo that stated the reason for fighting in Vietnam was based far more on preserving U.S. prestige than preventing communism or helping the Vietnamese.

Princeton University historian Sean Wilentz rejects similaries between WikiLeaks and the Pentagon Papers.

"It's not as if we're still up against the Vietnam War; and everybody has a right -- no a duty, to play Daniel Ellsberg," Wilentz, whose books include "The Rise of American Democracy" and "The Age of Reagan," said.

"But this is extremely dangerous, given the imperatives of diplomacy. Is there some profound deception of the American people and the world going on which, as with Ellsberg, requires an insider to, in effect, blow the whistle? I don't get that sense. I get the sense that there are people out there, like the WikiLeaks people, who have a simpleminded idea of secrecy and transparency, who are simply offended by any state actions that are cloaked."

But Ellsberg believes there are parallels to the documents he leaked nearly 40 years ago. He says that while early media reports about WikiLeaks focused on gossip and personalities, memos are now emerging that show greater U.S. involvement in Pakistan than the government acknowledged, a pattern revealed by the Pentagon Papers about Vietnam.

"This means the Obama administration is on a path that is as dangerous as can be," Ellsberg says, noting Pakistan's nuclear capabilities. "I think the press did a disservice by leading with so much gossip, which isn't terribly important."

Gabriel Schoenfeld, a former senior editor at Commentary magazine and author of "Necessary Secrets: National Security, the Media, and the Rule of Law," says WikiLeaks will have a "huge downside for historians" because it will encourage more secrecy. But he also wishes he had the chance to include WikiLeaks in his book and examine how a "nonstate actor" could "challenge frontally the U.S. security system."

John Dower, author of the Pulitzer Prize-winning "Embracing Defeat" and the National Book Award finalist "Cultures of War," praised WikiLeaks. "Embracing Defeat," a history of Japan after World War II, and "Cultures of War," a comparison between the George W. Bush administration and the Japanese leadership before Pearl Harbor, are both books about understanding how one's foes think and the dangers of unchallenged opinions.

"The public benefits by understanding what's going on," Dower says. "The government is bending over backward to be secretive. We need to understand what is taking place and how we are perceived by others. In recent years, we've had failure of intelligence and failures of imagination. We don't understand the other side. We don't know why people are being drawn to the terrorists."

"I don't see any reason to be worried about WikiLeaks. The government has all kinds of secrets, secrets that no leaker will ever get close to," said Seymour Hersh, the author and Pulitzer Prize-winning investigative reporter known for uncovering the My Lai Massacre during the Vietnam War and for his reports on the planning for the war in Iraq and the alleged torture of detainees at the Abu Ghraib prison.

"There will always be a struggle between what the government knows and what the public can find out. That's the reporter's job, to find out. What's happening now is about free expression. It's the First Amendment. It's the First Amendment. It's the First Amendment."