The CIA says it's been able to foil an Al Qaeda plot to get a bomb onto a plane headed to the U.S., but here in the metropolitan area with the highest number of air travelers in the country, there are a couple of disturbing details related to the plot: one, the alleged lead Al Qaeda bombmaker is still at large, and may be instructing more followers in sophisticated bombmaking techniques; two, the head of the country's largest police anti-terror operation, NYPD Commissioner Ray Kelly, warns against feeling overly secure when you fly.

"We live in a dangerous world, " Kelly said at a newsconference in response to a question from PIX11 News about assuring safety for airline passengers. "I can't give assurances in this day and age," he said.

At the same time, the police commissioner tried to assure that to whatever extent his force can ensure safety against terrorism it is providing it. At a news conference at police headquarters. "We are always devoted to counter-terrorism here [in New York], Kelly said at the police headquarters news conference. "We have over 1,000 officers specifically devoted to counter-terrorism. we think we're doing all that we can to protect the city."

The New York metropolitan area's three main airports accommodate more than 105 million passengers per year. That averages to 287,000 passengers daily, all of whom fly safely virtually all of the time. However, it only takes one flight with a successful terror attack on board to make all of the more than 45,000 daily flights worldwide seem threatened.

The CIA interception of what it called a new underwear bomb plot specifically prevented one flight from threatening everyone's security. Investigators from the intelligence agency and the CIA have said that an employee of the CIA -- an intelligence mole -- infiltrated a bomb-making ring in Yemen, headed by Ibrahim al-Asiri, who is suspected of manufacturing the underwear bomb worn by Umar Farouk Abdulmutallab when he was seized by passengers on a Christmas Day flight from Amsterdam to Detroit in 2009.

In the latest case, the CIA employee was able to seize the device and get it in the hands of U.S. investigators. It had no metal parts. "Which makes it very difficult [to detect]," Commissioner Kelly said. "So many of our detection systems are looking for metal."

He said he was confident that airport screeners could still find any explosive device before it got onto a plane. Prominent national security leaders agreed, but pointed out that there is no reason to assume total security.

"This seems to be a new level of sophistication by Al Qaeda," Rep. Peter King (R-Long Island) said in an interview. " It's an indication that the war, unlike the president said, is not going to end in Afghanistan. The war will go on for many years."

King also worries that the leak from this operation may compromise future overseas operations with other nations. It may also affect other nations willingness to cooperate in with the United States in covert missions.

PIX11 asked the TSA, which screens air cargo and passengers, and the Port Authority, whose police department patrols the Tri-State's airports, to comment about their ability to guard against an airline bomb. Neither agency responded to PIX11's requests.