At ataturk airport passengers pass through metal

At Ataturk airport, passengers pass through metal detectors and their bags are scanned as they
enter the terminal.
This differs from the procedures at most American airports, where anyone can enter the terminal
without being screened.
Turkish officials said the attackers initially tried to enter the building, but were turned away at
the security screening.
They returned with "long-range rifles" from their suitcases. Two of the attackers entered the
terminal in the ensuing panic.
One set off his explosives on the arrivals floor of the terminal; the other detonated his on the
departures floor one level above. A third attacker blew himself up outside the terminal as people
fled.
"Attempting to 'protect' against mass casualty attacks is a somewhat hopeless task due to the near
infinite number of targets," said Mark Stewart, a professor at the University of Newcastle in
Australia who studies how to protect infrastructure from terrorist attacks.
"A deterred terrorist will just go elsewhere," he said.
The Ataturk airport reopened on Wednesday with additional security measures: More cars are
being screened and more security officers are visible.
In the attack at Brussels Airport in March, there was no security check at the terminal entrance.
The attackers entered the building and detonated their explosives.
Since that attack, the airport began checking the boarding passes and IDs of passengers entering
the departures terminal.
In addition, the airport no longer allows travelers to be dropped off at the terminal. They must be
dropped off at parking lots nearby.
At American airports, passenger screening checkpoints are the responsibility of the
Transportation Security Administration.
The agency received intense criticism a month ago over long lines at airports across the United
States. The wait for security screening stretched to more than three hours at times, and thousands
of passengers missed flights.
There are trade-offs to increasing security and adding checkpoints, said John Mueller, a professor
of political science at Ohio State University, who studies terrorism and security.
"The T.S.A. has created a target with security lines," Mr. Mueller said, pointing to the long
security lines. He suggested that programs that speed up screening like T.S.A. PreCheck be more
widely adopted.
Less crowding could be critical to reducing casualties in a terrorist attack.
A RAND Corporation analysis of Los Angeles International Airport found that decreasing the
wait at baggage check-in to one minute from 15 minutes could reduce the number of deaths in a
bomb attack by more than half.
Security at Charles de Gaulle Airport in Paris is similar to that of American airports. There is no
security screening in public areas like access roads, parking lots or terminal entrances, but armed
soldiers patrol the areas.