The deadly terror attack at Turkey's largest airport has posed an all-too-familiar question to security officials: how to protect passengers and bystanders from such carnage?

The attackers arrived via taxi like many other passengers to Istanbul's busy Ataturk Airport on Tuesday night. Unlike others, however, their journeys ended in a wave of bloodshed that killed 41 people and wounded hundreds of others in an attack that security analysts say was nearly impossible to stop.

"Whether you kill nearly 50 people in or outside of the airport is really just a matter of semantics," said Matthew Henman, managing editor at IHS Jane's Terrorism and Insurgency Centre. From an economic and security standpoint, it would be unfeasible to entirely prevent an armed attack without severe cost and disruption — especially at a busy airport like Ataturk."

Airports around the globe have been bolstering security since the 1970s following terror attacks. Israel was one of the first to take steps after attackers in 1972 killed 26 people and injured 80 at Lod Airport, now Ben Gurion Airport. Airport security was also strengthened at many points around the world following the Sept. 11 terror attacks in 2001, and in 2006, when British and American intelligence agents uncovered a plot to smuggle liquid explosives through security in an attempt to blow up trans-Atlantic airliners.

The latter resulted in precautions which still prohibit passengers from bringing certain quantities of liquids and gels through security. The most recent attack occurred in March when three coordinated bombings rocked the Brussels Airport in Zaventem and the Maalbeek metro station. In those attacks, claimed by the Islamic State group, 32 were killed and more than 300 wounded.

In Israel's case, a generous state budget allows for some 2,000 personnel to work exclusive in airport security roles, and many of those workers are undercover, according to Pini Schiff, CEO of Israel Security Association, one of Israel's top aviation security experts. Passengers are also checked via radar, cameras and other equipment well before they enter the airport and laws allow for ethnic profiling, he said.

"In the Turkey case, it seems authorities were completely caught by surprise," Schiff said. "It appears this attack took weeks to plan."

CIA Director John Brennan said the attacks bore the hallmarks of the Islamic State group and warned that the group wants to conduct similar attacks in the United States. The Turkish government blamed IS, but the group didn't immediately claim responsibility.

"I am worried from the standpoint of an intelligence professional who looks at the capabilities of Daesh . and their determination to kill as many people as possible and to carry out attacks abroad," Brennan said in an interview with Yahoo News. Daesh is an acronym for the Arabic name of the Islamic State group, also known as ISIS or ISIL.

Brennan credited effective homeland security measures and intelligence for the fact that the Islamic State group has been unable to attack America directly — the Orlando and San Bernardino shootings were carried out by radicals inspired by the group but not under its control — but he believes the group will keep trying to penetrate American defenses.

Jeffrey Price, who teaches at Metropolitan State University of Denver and wrote a textbook on aviation security, said that Ataturk's security was considered good, with layers that extended beyond the checkpoints.

"They may find that airport security did all they could" but that intelligence agencies failed to identify and stop the attackers before they could act, he said.

The lesson for other airports, Price said, is to have enough armed police to regularly patrol public spaces and to keep checkpoint lines moving so that crowds don't build in vulnerable areas outside the security perimeter.

In the United States, that means that the Transportation Security Administration must balance its job of keeping dangerous items off planes with the need to move travelers through checkpoints quickly, he said.

"The aviation-security industry has been saying for years that eventually someone is going to figure out that 500 people standing in line at the checkpoint is just as good a target as if they get through (the checkpoint) and get to an airplane," he said.

Kenneth J. Button, director of the Center for Transportation, Policy, Operations and Logistics at George Mason University, says airports are prime targets. Ataturk is one of the world's busiest airports drawing tourists from around the globe.

"There is no solution. There are ways of limiting attacks," Button said. "But none are foolproof."

Anthony Roman, a security expert who runs a consulting firm in Lynbrook, New York, said it appeared that the attack began outside of the secure area and might have done great damage even without getting deep into the terminal.

"This is a sophisticated attack on the airport which brings to light some of the shortcomings of American airport security," he said. "We are vulnerable to easy penetration of the arrivals and departures terminals where large numbers of people gather for ticketing, for baggage claim, and for TSA screening itself."

Roman said Turkish airports usually begin screening cars before they get to the terminal. Roman said major airports should have rings of security, starting with officers to watch vehicles entering the airport and pull over any that seem suspicious or out of the ordinary. Passengers too should be watched and if necessary pulled aside before they get inside the terminal.

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Ian Deitch reported from Jerusalem, David Koenig from Dallas and Scott Mayerowitz in New York.