The scene in the parking lot at the National Security Agency yesterday was something akin to a pep rally. President Bush, in a two-hour visit, chatted spiritedly with employees, signed autographs and thanked them for helping to hunt terrorists.

"We'll get 'em!" Bush proclaimed to his cheering audience, according to an employee at the top-secret Fort Meade agency who heard the president speak at the private event.

It was a far cry from Capitol Hill, where lawmakers were launching an aggressive inquiry into how the intelligence agencies missed warning signs of the Sept. 11 attacks.

Earlier, Bush told reporters that he had come to express gratitude to "those who sacrifice on behalf of our nation." The congressional investigation, he insisted, was not dampening the spirits of rank-and-file workers here, or at the CIA or FBI.

"I believe morale is high," Bush said. "Our intelligence communities understand they are on the forefront of one of the most important wars in our nation's history. I think I'm more worried about them being overworked. These good people are putting in long, long hours."

After Sept. 11, some NSA employees began working nearly round-the-clock to try to pinpoint Osama bin Laden and his al-Qaida operatives. The NSA is the agency responsible for intercepting and decoding encrypted communication signals from around the globe.

As he spoke with reporters, Bush stood beneath a banner that read: "We won't back down. We never have. We never will."

The banner was put up by NSA officials soon after Sept. 11 to rally employees. Some analysts have said the NSA failed to intercept terrorists' communiques about the attacks.

The president acknowledged yesterday that reforms are needed in the intelligence agencies. At the same time, he seemed determined to heap praise on rank-and-file employees of the beleaguered intelligence arm of the government.

Bush is the first president to visit the NSA since his father, who spoke to employees at the end of the Persian Gulf war.

While the FBI and CIA have borne the bulk of criticism for U.S. intelligence lapses, the NSA is certain to absorb scrutiny as congressional hearings wear on. Just days after Sept. 11, both the House and Senate released scathing reports, long in the works, asserting that budget cuts and mismanagement at the NSA could weaken the fight against terrorism.

Reporters and photographers who accompanied the president were barred from approaching NSA employees, many of whom lingered nearly 20 minutes along a rope line to try to shake Bush's hand or get his autograph.

The president's remarks to employees, delivered from a platform in the agency's sun-drenched parking lot, were off-limits to reporters.

A White House official who heard Bush speak said one of his messages was that the "right equipment and the best computers" are meaningless in an agency like the NSA without "the dedication and brainpower of the people."

An NSA employee, speaking on condition of anonymity, said Bush was upbeat and at times comical. The president, he said, told employees they were performing admirably and should continue on the same path.

And, the employee added, "people loved him."

Sun staff writer Laura Sullivan contributed to this article.