It's been three years since the Sept. 11 attacks, and Americans observed the anniversary with memorials, prayers and debate. Is the country any safer today from the threat of terrorism than it was then? Did President Bush do the right thing in launching a war against Iraq, and was it worth the price? Author Seymour Hersh doesn't think so. He believes that somewhere over the past three years the Bush administration took a very wrong turn. In his new book, "Chain of Command," he tells the story of a top secret intelligence unit that he says answers directly to the highest levels of the Pentagon and how its early successes led to shameful excesses that dealt a serious blow to America's war on terror. Read an excerpt below:

In May 2004, at the height of the Abu Ghraib prison abuse scandal, a senior political Republican Party operative was given the reassuring word that Vice President Dick Cheney had taken charge, with his usual directness. The operative learned that Cheney had telephoned Donald Rumsfeld with a simple message: No resignations. We're going to hunker down and tough it out.

Cheney's concern was not national security. This was a political call-a reminder that the White House would seize control of every crisis that could affect the re-election of George Bush. The Abu Ghraib revelations, if left unchecked, could provoke more public doubt about the wisdom of the war in Iraq, and about the sometimes brutal intelligence operations that were used to wage it. The White House and Pentagon also would have to work together to prevent Congress and the press from unraveling an incendiary secret-that undercover members of an intelligence unit that operated in secret in the name of every American had been at Abu Ghraib. The senior leadership in

the White House has been aware since January of the mess at Abu Ghraib, and, more importantly, of the fact that photographs and videotapes existed, and might someday reach the public. As we have seen, the military chain of command had ignored the possibility of higherup involvement and moved quickly to prosecute the military police who had committed the acts-"the kids at the end of the food chain," as a former senior intelligence official put it: "We've got some hillbilly kids out of control."

The perception persists that this was Rumsfeld's war, and that it was his assertiveness and his toughness that sometimes led to the bombing of the wrong target or the arrest of innocents. But Cheney's involvement in trying to conceal the import of Abu Ghraib was not unusual; it was a sign of the teamwork at the top. George Bush talked about "smoking them out of their holes" and wanting them "dead or alive," and Rumsfeld was the one who set up the mechanism to get it done. The defense secretary would hold the difficult news conferences and take the heat in public, as he did about Abu Ghraib, but the President and Vice President had been in it, and with him, all the way. Rumsfeld handled the dirty work and kept the secrets, but he and the two White House leaders were a team.

There is so much about this presidency that we don't know, and may never learn. Some of the most important questions are not even being asked. How did they do it? How did eight or nine neoconservatives who believed that a war in Iraq was the answer to international terrorism get their way? How did they redirect the government and rearrange long-standing American priorities and policies with so much ease? How did they overcome the bureaucracy, intimidate the press, mislead the Congress, and dominate the military? Is our democracy that fragile? I have tried, in this book, to describe some of the mechanisms used by the White House-the stovepiping of intelligence, the reliance on Ahmad Chalabi, the refusal to hear dissenting opinions, the difficulty of getting straight talk about military operations gone bad, and the inability-or unwillingness-of the President and his senior aides to distinguish between Muslims who supported terrorism and those who abhorred it. A complete understanding of these last few years will be a challenge for journalists, political scientists, and historians.

Many of the failings, however, were in plain sight. The Administration's manipulation and distortion of the intelligence about Iraq's ties to Al Qaeda and its national security threat to the United States was anything but a secret in Washington, as the pages of this

book make clear. And yet the Republican-led Senate Intelligence Committee, after a year-long investigation, published a report, in July 2004, stating that the critical mistakes were made not in the White House, but at the C.I.A., whose analysts essentially missed

the story. There was an astonishing postscript that told much about the disarray in Washington. Three Democrats, John D. Rockefeller IV of West Virginia, the vice chairman of the committee, Carl Levin of Michigan, who is also the ranking Democrat on the Armed Services Committee, and Richard Durbin of Illinois, signed a separate statement disavowing the report's central findings. "Regrettably, the report paints an incomplete picture of what occurred during this period of time," they wrote, noting that the "central issue" of how intelligence was misused by the Administration and the pre-war role of Ahmad Chalabi would be included in a second report-one that was not to be made public until after the presidential election. "As a result," they wrote, "the Committee's phase one report fails to fully explain the environment of intense pressure in which Intelligence Community officials were asked to render judgments on matters relating to Iraq, when policy officials had already forcefully stated their own conclusions in public."

And yet, Rockefeller, Levin, and Durbin put their names on the report, helping to make it appear unanimous and bipartisan. There are, once again, unanswered questions. Why didn't the Democrats take a stronger stand? How much influence did the White House exert on the Republican members of the committee? Why didn't the press go beyond the immediate facts? The inner workings of the committee were in many ways a more important story than its findings.