In an already hot presidential election year, the White House is readying itself for Thursday's release of the Sept. 11 commission's 500-plus-page report, which is expected to detail significant intelligence lapses surrounding the deadly attacks on the United States.

"A president and a Congress must get the best possible intelligence about how to protect America and its allies," President Bush told reporters Wednesday while meeting with Romanian Prime Minister Adrian Nastase, saying he welcomed the report.

"Had we had any inkling whatsoever that terrorists were about to attack our country, we would’ve moved heaven and earth to protect America," the commander-in-chief said. "I'm confident President Clinton would have done the same thing — any president would."

The president earlier signed a bill at the White House to develop and stockpile vaccines and other antidotes to biological and chemical weapons and said his administration is doing everything possible to prevent another attack.

The Sept. 11 commission (search) should talk about the need for more human intelligence, the president said, since that's "one of the most effective ways for us to gather intelligence in the first place." Using modern technology to better listen and see events in real time will also help America protect itself, Bush added, saying a "full discussion" on how to better coordinate intelligence agencies is also needed.

What the report won't say, however, is that the events that left about 3,000 people dead could have been prevented. The White House wouldn't have accepted that conclusion.

"The fact of the matter is: We were not on war footing prior to Sept. 11. Now we are a nation at war," White House spokesman Scott McClellan said Wednesday. "We are engaged in a global War on Terrorism. But the threat from terrorism was building for more than a decade."

Commission Chairman Thomas Kean (search), a former New Jersey governor, and Democratic Vice Chairman Lee Hamilton (search), a former Indiana congressman, briefed Bush's national security adviser, Condoleezza Rice, and White House counsel Alberto Gonzalez Wednesday on the panel's findings.

It's Not About Politics

The report will be "a measure about whether we have taken changes in the meantime [since Sept. 11, 2001] to make sure it can't happen again and to make sure these agencies are cooperating … whether we've taken enough action has yet to be analyzed," Sen. Charles Grassley, R-Iowa, told FOX News on Wednesday, noting that the FBI and CIA are already talking more now than they were on Sept. 10, 2001.

Sen. John Corzine, D-N.J., told FOX News that the report should be null and void of politics.

"For those who want to turn it into a program of political argument in a political season — I think they're doing a disservice to the people who lost their lives on 9/11," he said. "This isn't about Republicans or Democrats. This is about making sure our national security and homeland security are absolutely in top shape as we go forward."

The report includes a list of 10 "operational opportunities" that the government missed to potentially unravel the plot, a government official told The Washington Post. Six of the incidents listed apparently came during the Bush administration and four were during the Clinton years.

"When you say it's preventable, as the leaks were suggesting a few months ago … that sounds like you're really blaming the Bush or Clinton administrations for dereliction of duty or poor performance," said Michael O'Hanlon, senior fellow at The Brookings Institution. While it's not theoretically impossible the attacks could have been prevented, O'Hanlon said, "It would have taken very good work" to stop them.

Another government official told The Washington Post that the tally of missed opportunities includes the CIA's failure to add two hijackers' names to a terrorism watch list; the FBI's handling of the August 2001 arrest of Zacarias Moussaoui (search), who has been accused of conspiring in the Sept. 11 plot; and several failed attempts to kill or capture Usama bin Laden.

The report also is expected to highlight more ties between Iran and Al Qaeda and just how freely known terrorists move in and around that country.

"We know there are Al Qaeda in Iran — senior Al Qaeda, and there have been for some time. We know that Iran has been helping Hezbollah in moving terrorists down through Syria into Lebanon and then down into Israel," Defense Secretary Donald Rumsfeld told reporters Wednesday.

Rumsfeld said he hopes the report identifies problems before "we start rushing around and moving boxes around … to have solutions to things we've not identified."

New Intel Chief Proposed

The panel of five Republicans and five Democrats also will call for a controversial new Cabinet-level intelligence chief and recommend combining the House and Senate intelligence committees and removing term limits from committee members.

The panel will cite poor information-sharing and intelligence analysis in the FBI and CIA as key factors that allowed the 19 hijackers to carry out their deadly plot.

Bush on Wednesday wouldn't venture an opinion on that, he said, until he studied the report. Aides say he is also awaiting a report from his commission on weapons of mass destruction proliferation.

Sen. Arlen Specter, R-Penn., told FOX News that such an intelligence post has been necessary for some time.

Of the CIA and FBI, he said, "the fact is, both of those agencies have cultures of concealment — they just don't share information."

Intelligence agencies will "fight it fiercely," Specter said of the czar position, and there's already opposition to such an idea on Capitol Hill because some committees may have to give up some oversight.

"It's time we stopped worrying about power and started to worry about the security of the American people," Specter said.

House Speaker Dennis Hastert said Congress isn't likely to undertake major revisions of the nation's intelligence operations this year. Sept. 11 commissioners plan an aggressive lobbying effort in the summer and fall to push recommended changes.

'Broken' Intelligence System

Panel chairmen have said the attacks conceivably could have been prevented but in the end, the commission didn't want to say that in an effort to avoid more partisan sniping.

Some Republican lawmakers said Tuesday that because the Bush administration had only been in office eight months before the attacks, the Clinton administration bears most of the responsibility for events leading up to Sept. 11.

Democrats, who were briefed on the report Thursday, disagree.

"Yes, it happened on President Bush's watch, but this report was not there to assign blame, it was to say: What is it in our communication within our security, our law enforcement and security entities, the FBI, the CIA, etc. … what is it within their organizations that needs to be fixed to have accountability and communication?" asked House Democratic Leader Nancy Pelosi of California.

Advisers to Democratic presidential candidate John Kerry have said they hope to use the report to show that in the summer of 2001, the Bush administration was inattentive to threats of a possible attack.

"I think in the end, the American people are going to hold George Bush accountable for what happened after 9/11, not before 9/11," such as how the White House "oversold" evidence of Iraq's weapons of mass destruction, former Clinton assistant counsel Jeff Connaughton told FOX News.

FOX News' Bret Baier, Wendell Goler and The Associated Press contributed to this report.