Peter Bergen is CNN's national security analyst, a vice president at New America and a professor of practice at Arizona State University. He is the author of "The Longest War: The Enduring Conflict Between America and al-Qaeda," which this piece draws upon.

(CNN) It's not often that one gets the chance to write the following: Donald Trump is right.

Trump, of course, has been very wrong in the past about important issues such as President Barack Obama's place of birth and Mexican immigrants, but the Republican frontrunner is correct in saying that former Republican President George W. Bush did not keep the country safe during the 9/11 terrorist attacks.

On Monday Trump told Fox News, "The fact is we had the worst attack in the history of our country during his reign. Jeb (Bush) said we were safe during his reign. That wasn't true."

The historical record bears this out.

A visitor tours the crash site at the Flight 93 National Memorial on September 10. The visitor center complex was dedicated in honor of the victims of Flight 93 on the evening of the 14th anniversary of the 9/11 attacks.

A visitor tours the crash site at the Flight 93 National Memorial on September 10. The visitor center complex was dedicated in honor of the victims of Flight 93 on the evening of the 14th anniversary of the 9/11 attacks.

Some 3,000 flags erected by Pepperdine University students and staff honor the victims of 9/11 on the Malibu, California, on September 10.

Some 3,000 flags erected by Pepperdine University students and staff honor the victims of 9/11 on the Malibu, California, on September 10.

Yachiyo Kuge carries a lantern to place at the Wall of Names at the Flight 93 National Memorial in Shanksville, Pennsylvania, on Thursday, September 10. Kuge is the mother of Toshiya Kuge, a Japanese passenger who died on United Airlines Flight 93 on 9/11. The plane crashed in Pennsylvania as passengers and crew tried to overcome the hijackers.

Yachiyo Kuge carries a lantern to place at the Wall of Names at the Flight 93 National Memorial in Shanksville, Pennsylvania, on Thursday, September 10. Kuge is the mother of Toshiya Kuge, a Japanese passenger who died on United Airlines Flight 93 on 9/11. The plane crashed in Pennsylvania as passengers and crew tried to overcome the hijackers.

Terry Miller, right, and Chris Miller, center, look for the name of their brother Robert Cromwell Miller at the Empty Sky memorial to New Jersey's victims of 9/11. The memorial is in Jersey City across the Hudson River from the World Trade Center site. Nephew James Miller, left, joins them Friday.

Terry Miller, right, and Chris Miller, center, look for the name of their brother Robert Cromwell Miller at the Empty Sky memorial to New Jersey's victims of 9/11. The memorial is in Jersey City across the Hudson River from the World Trade Center site. Nephew James Miller, left, joins them Friday.

Roses are placed Friday at the National September 11 Memorial in New York before a ceremony commemorating the 14th anniversary of the attacks.

Roses are placed Friday at the National September 11 Memorial in New York before a ceremony commemorating the 14th anniversary of the attacks.

President Barack Obama and first lady Michelle Obama lead a moment of silence on the White House South Lawn at 8:46 a.m. Friday -- the time when the first hijacked plane hit the World Trade Center on 9/11.

President Barack Obama and first lady Michelle Obama lead a moment of silence on the White House South Lawn at 8:46 a.m. Friday -- the time when the first hijacked plane hit the World Trade Center on 9/11.

Engine Company 205/Ladder Company 118 in New York's Brooklyn Heights remember the eight firefighters it lost on 9/11, including six who died in their firetruck under the rubble.

Engine Company 205/Ladder Company 118 in New York's Brooklyn Heights remember the eight firefighters it lost on 9/11, including six who died in their firetruck under the rubble.

Law enforcement officials stand at attention Friday during the national anthem in an anniversary ceremony in New York in commemoration of the 9/11 attacks.

Law enforcement officials stand at attention Friday during the national anthem in an anniversary ceremony in New York in commemoration of the 9/11 attacks.

Gary Mascitis, 14, pays tribute to his uncle during an anniversary ceremony for the attacks in New York. Two hijacked planes hit the World Trade Center on 9/11. A third plane crashed into the Pentagon outside Washington and a fourth into a Pennsylvania field.

Gary Mascitis, 14, pays tribute to his uncle during an anniversary ceremony for the attacks in New York. Two hijacked planes hit the World Trade Center on 9/11. A third plane crashed into the Pentagon outside Washington and a fourth into a Pennsylvania field.

The sun rises over Lower Manhattan and One World Trade Center, at left, on Friday, September 11, in a view from Jersey City, New Jersey. The nation is marking the 14th anniversary of 9/11, the deadliest terrorist attack on U.S. soil. Nearly 3,000 people died that day. See other images of 9/11 events:

The sun rises over Lower Manhattan and One World Trade Center, at left, on Friday, September 11, in a view from Jersey City, New Jersey. The nation is marking the 14th anniversary of 9/11, the deadliest terrorist attack on U.S. soil. Nearly 3,000 people died that day. See other images of 9/11 events:

Before 9/11 senior Bush administration officials did not see al Qaeda as the serious threat it was, despite the fact that the group had blown up two American embassies in Africa in 1998, killing more than 200 people, and had also bombed the USS Cole warship two years later. Also, they ignored multiple, clear warnings from the CIA during the summer of 2001 about a likely al Qaeda attack, although those warnings did not specify where that attack might happen.

A Nexis database search of all newspapers, magazines, and TV transcripts for anything that President Bush or Vice President Dick Cheney might have written or said about the threat posed by al Qaeda and bin Laden comes up completely empty before 9/11.

Of the 33 "principals" meetings of cabinet members held by the Bush administration before the attacks, only one was about terrorism, although almost immediately after assuming office on February 5, 2001, Bush convened his cabinet to discuss the supposedly pressing issue of Saddam Hussein's regime in Iraq.

The first cabinet-level meeting about the threat posed by al Qaeda took place only a week before 9/11, on September 4, 2001.

Al Qaeda threat barely registered

Bush administration officials, of course, deny that they didn't take the threat urgently enough, but there is no debating that in their public utterances, private meetings, and actions, the al Qaeda threat barely registered.

Part of the explanation for this is that key members of the Bush national security team team had cut their teeth during the Cold War. Bush's top national security adviser, Condoleezza Rice, was a Soviet specialist at the National Security Council under President George H.W. Bush, while Cheney had served as White House chief of staff during the Ford administration. Their views about the importance of state-based threats remained frozen in a Cold War mindset.

To admit that non-state terrorists were a real danger to the nation, it then became harder to argue, as many in the administration did, that a rogue state, Iraq, was the number-one overriding danger.

The inattention of the Bush administration to the threat from al Qaeda had results. Shortly before 9/11, Bush's attorney general, John Ashcroft, turned down FBI requests for some 400 additional counterterrorism personnel. Ashcroft also told Justice Department officials in early 2001 that his top priorities included tamping down gun violence and curtailing teen drug use.Terrorism wasn't one of them.

On October 12, 2000, the USS Cole was attacked in the Yemeni port city of Aden by al Qaeda suicide bombers, an operation that killed 17 American sailors and threatened to sink the billion-dollar destroyer.

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Following the Cole attack the Clinton administration, in office for only three more months, did nothing to respond. This was despite the fact that according to the Ali Soufan, the lead FBI agent on the Cole case, within three weeks, "We knew one hundred percent that it was bin Laden."

On December 21 the CIA made a presentation to the key national security officials in the Clinton cabinet that there was a "preliminary judgment" that al Qaeda aided the Cole attack.

By the time the Bush administration was sworn into office in January 2001, it was obvious that al Qaeda was responsible for the Cole bombing. On February 9 Vice President Cheney was briefed that the attack was the work of bin Laden's men.

In June 2001 al Qaeda released a propaganda videotape strongly implying its responsibility for the Cole operation and calling for more anti-American attacks. If the Bush administration needed a casus belli, here it was broadcast around the world. The attack on the Cole was an act of war, plain and simple, and it merited an American military response.

The feckless response to the Cole attack was a bipartisan failure.

'Blinking red'

During the summer of 2001 CIA Director George Tenet told the 9/11 Commission that the American intelligence "system was blinking red" because of a series of credible intelligence reports about al Qaeda's plans for attacks on American targets.

Below is a representative sampling of the threat reporting that was distributed to Bush officials, which gathered intensity during the spring and reached a crescendo during that summer.

• CIA: "Bin Ladin Planning Multiple Operations," April 20

• CIA: "Bin Ladin Attacks May Be Imminent," June 23

• CIA: "Planning for Bin Ladin Attacks Continues, Despite Delays," July 2

• CIA: "Threat of Impending al Qaeda Attack to Continue Indefinitely," August 3

On July 10 Tenet took the unusual step of calling Rice and asking her with some urgency for a meeting that same day to discuss the al Qaeda threats. Barely 15 minutes later, Tenet and two of his deputies were in Rice's White House office. One of Tenet's staff got everyone's attention when he predicted, "There will be a significant terrorist attack in the next weeks or months ... Multiple and simultaneous attacks are possible and they will occur with little or no warning."

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Rice asked her counterterrorism adviser Richard Clarke if he shared this assessment and he gave an exasperated "Yes."

Rice would later publicly testify before the 9/11 Commission that the Bush administration was at "battle stations" during this period. The historical record does not reflect this.

The 'determined to strike' briefing

During August, Bush was at his vacation ranch in Crawford, Texas. On August 6 he was given an intelligence briefing titled "Bin Ladin Determined to Strike in U.S." The brief began by noting, "Clandestine, foreign government, and media reports indicate Bin Laden since 1997 has wanted to conduct terrorist attacks in the US."

The brief had been prepared, in part, by the veteran CIA analyst 'Barbara S.' an agency official who had tracked al Qaeda for years. Bush later said the contents of the brief were only "historical" and told him nothing new about the danger from al Qaeda.

Barbara S., now revealed to be Barbara Sude, says the President did not understand the intention of the briefing, which was to warn of a possible attack in America, not to rehash past history. Sude told me, "Was the piece historical? No ... So did the analysts think that something would happen in the United States? We did assess there was a major attack coming. We couldn't say definitively where. We had threats all year about various locations."

Sude says that the CIA briefing was particularly influenced by the fact that just two month earlier, Ahmed Ressam, an Algerian on the fringes of al Qaeda, had pled guilty to charges that he had planned to detonate a bomb at Los Angeles International Airport in the middle of the Christmas season of 1999.

Following the August 6 briefing, President Bush never publicly discussed the threat posed by al Qaeda until after 9/11, and chose not to interrupt what the Washington Post described as being the longest presidential vacation in more than three decades.

The 9/11 Commission also found no evidence that he had any further discussions with his advisers about possible al Qaeda attacks on the United States until after they had happened.

Al Qaeda intentions were no secret

Despite Rice's testimony before the 9/11 Commission that the Bush administration was at battle stations during the summer of 2001, in a wide-ranging and emblematic interview with Fox News the night of August 6 -- the same day that President Bush had been briefed that bin Laden might attack the States — Rice chose to discuss the troubled situation in Israel, the administration's missile defense plans, and its relations with Russia. The threat from al Qaeda, bin Laden and terrorism went unmentioned.

There is also no evidence that Rice did anything to "pulse" the national security system for additional information about the presence of jihadist militants in the United States. Might that have caused the information about Zacarias Moussaoui, an al Qaeda recruit then in FBI custody in Minnesota who was keen on practicing flying a 747, to have been more widely distributed? Might that have caused the wider dissemination of the names of al Qaeda's soon-to be-hijackers Nawaf al Hazmi and Khalid al Mihdhar, who were known by the CIA to be in the United States?

It is worth contrasting Rice's lackadaisical approach with that of Clinton's national security adviser, Sandy Berger, who held almost daily meetings of the National Security Council from mid-December 1999 as the new millennium approached and similar fears of a terrorist attack gripped the national security establishment.

The fact that al Qaeda and its allies intended to attack the United States, and indeed had already done so before 9/11, was hardly a secret. The CIA briefing to President Bush headlined "Bin Ladin Determined to Strike in the U.S." was simply stating the blindingly obvious.

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Al Qaeda's leader had repeatedly said he was going to attack the United States, starting in 1997 in an interview with CNN, and he reiterated this threat over the next two years in interviews with ABC News and Time.

Rarely have the enemies of the United States publicly warned so often of their plans. Imagine for a moment that starting in 1937, Japanese government officials had repeatedly told American radio and newspaper correspondents that they were planning to strike the United States. Might not the events of Pearl Harbor have played out rather differently than they did on the morning of December 7, 1941?

The problem, then, was not a lack of information about al Qaeda's intentions and capabilities, but the Bush administration's inability to comprehend that an attack by al Qaeda on the United States was a real possibility, much more so than attacks by traditional state antagonists such as China or Iraq.

This was a policy failure by the Bush administration, not, as many Americans believed in the years after 9/11, an intelligence failure. Indeed the CIA did an excellent job during the summer of 2001 of repeatedly warning senior Bush officials that al Qaeda was planning a major attack. Where and when that attack was going to happen was, of course, not known.