Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, said there was concern that potential extremists could be inspired by the failed bombing attempt blamed on 23-year-old Umar Farouk Abdulmutallab.
Al Qaeda in the Arabian Peninsula has claimed responsibility for the attempt, one of the most serious U.S. security breaches and intelligence breakdowns since the September 11 attacks.
Certainly there is the concern that this would bring more, generate more support from young males who might be on the fence about what to do with their lives, Mullen said.
A grand jury in Michigan indicted Abdulmutallab on six counts, including attempted murder of the other 289 passengers and crew on board the plane, and attempting to use a weapon of mass destruction. He faces life in prison, if convicted.
The bomb, which Abdulmutallab has told investigators was given to him by al Qaeda in Yemen, contained the highly explosive ingredients Pentaerythritol Tetranitrate (PETN) and Triacetone Triperoxide (TATP), the indictment said.
U.S. Attorney General Eric Holder held out the possibility of others being charged, saying anyone we find responsible for this alleged attack will be brought to justice using every tool -- military or judicial -- available to our government.
Obama called the incident a potentially disastrous screw up by the intelligence community during a two-hour meeting with his national security team on Tuesday.
The president -- he's not patient about this at all. These changes have to be made immediately, Mullen told a group of university students at a seminar in Washington.
Obama will address the issue again in a public statement on Thursday, when the White House will release a review that will make recommendations on plugging holes in security, including changes in passenger screening and terrorism watch lists.
The review will simply identify and make recommendations as to what was lacking and what needs to be strengthened, White House spokesman Robert Gibbs said, adding it would be comprehensive.
U.S. spy agencies and the State Department had information about Abdulmutallab but they never pieced it together to put him on a no-fly list. Instead, passengers and crew subdued the Nigerian bomb suspect as he tried to detonate the bomb.
Mullen said part of the problem was intelligence sharing and filtering through the extraordinary amount of data collected by U.S. spy agencies.
It does have to do with sharing information and it does have to do with huge bureaucracies. And we collect an extraordinary amount of data, Mullen said.
Obama has been lambasted by Republicans who accuse his Democratic administration of being weak on terrorism and unable to fix intelligence gaps that have lingered since the September 11, 2001, attacks on the United States involving hijacked planes.
Since the Christmas bombing attempt, there has been finger pointing within the U.S. intelligence community, including at the National Counterterrorism Center, created in 2004 to serve as the main repository for counterterrorism intelligence.
Asked whether anyone might lose their jobs over the incident, Gibbs said: I don't know what the final outcome in terms of hiring and firing will be.
This is a failure that touches across the full waterfront of our intelligence agencies, he said.
Pentagon press secretary Geoff Morrell did not rule out the possibility the review could affect the Defense Department, but added he does not see any readily apparent failings within this department as to how we should have responded.
As for what this department in particular will do differently, I think that is something that is yet to be determined, Morrell told reporters.
(Additional reporting by Matt Spetalnick and Adam Entous; Editing by Philip Barbara)