Editor's note: Brian Michael Jenkins, senior adviser to the president at the RAND Corp., is the author of "Will Terrorists Go Nuclear?" (2008, Prometheus Books). He formerly was chair of the Political Science Department at RAND, a nonprofit research organization focusing on public policy, and founded its terrorism research program in 1972.
(CNN) -- The bombing of Moscow's Domodedovo Airport that killed 35 and wounded 152 was not the first of its kind in Russia.
Suicide bombers managed to beat security measures there in 2004 and bring down two airliners, killing 88 people. Despite extraordinary security measures, terrorists remain obsessed with attacking airline targets.
When faced with increased security, terrorists do not abandon commercial aviation as a venue for their violence. They attack airports instead, as the terrorists did Monday in Russia.
Attacks on airports give terrorists the symbolic value they seek and guarantee the attention of the international news media. They also create alarm locally. Russians now likely fear that a new operational terrorist cell is at large in Moscow while, internationally, tourists and business executives re-evaluate their travel plans.
Terrorist attacks on airports are not a new phenomenon. The first hijacking of any airliner by terrorists (it was not the first hijacking) occurred in 1968. The first terrorist bombing of an airliner by terrorists occurred in 1970. In 1972, three members of the Japanese Red Army, as part of its alliance with the Popular Front for the Liberation of Palestine, threw hand grenades and machine-gunned arriving passengers at Lod Airport in Israel, killing 26 and wounding 78, many of them Puerto Rican pilgrims on a visit to the Holy Land.
It was not merely the carnage that attracted worldwide attention. People asked, how is it that Japanese come to Israel to kill Puerto Ricans on behalf of Palestinians?
Forty years of terrorist attacks have prompted extraordinary security measures. These have had some success, or at least acted as a deterrent. As we see from the 2009 attempt by the so-called underwear bomber to bring down an airliner flying from Amsterdam, the Netherlands, to Detroit, and the 2010 attempts to sabotage air courier flights, some terrorists managed to smuggle explosive devices onto airplanes. But they were hampered by security and forced to build more concealable devices with less detectable firing mechanisms and smaller quantities of explosives. These devices didn't work. They probably would not have brought down a plane if they exploded midflight. Moreover, improved intelligence helps keep terrorists off airplanes.
Attempts by terrorists to hijack or bomb airliners have declined from an average of one a month in the 1970s to an average of one or two a year in the post-9/11 era.
Monday's attack at the Moscow airport is the worst since the massacre at Lod Airport (now called Ben Gurion International Airport) 39 years ago.
In 1975, a bomb exploded in the baggage claim area of LaGuardia Airport in New York, killing 14 and injuring 70. In 1983, a terrorist bomb killed five and wounded 56 at the check-in counter at Orly Airport in Paris. And in 1985, terrorists attacked passengers at the airports in Rome and Vienna, Austria, killing 13 and wounding 113.
Suspicious customs agents at the U.S.-Canadian border arrested a terrorist there in 1999. They discovered a large bomb in the trunk of his car, which he intended to detonate at the Los Angeles International Airport. Had he succeeded, the blast would have been devastating.
The question is inevitable: Do we need still more security for check-in counters, arrival halls and other easily accessible areas of the airport? The answer is that these public places are costly to protect and cannot be made impossible to bomb.
Even if a determined terrorist was deterred by a new ring of security at the entrance to the airport, he would not retire from terrorism. He would simply go a few miles farther to detonate his device at a train station, shopping mall, crowded restaurant or busy site such as New York's Times Square, all of which have been terrorist targets. The cost to protect public places is as significant as the disruption these measures would cause, with little net security benefit.
Some airports operate random checkpoints at the vehicle entrance to the airport to discourage terrorists from driving in with a huge truck bomb. And armed police or soldiers patrol the public areas of airports to conduct surveillance and to be able to respond rapidly if someone opens fire.
Moscow will probably increase these measures at Domodedovo Airport and the same will happen at major airports around the world. This may save some lives at airports, but adding another layer of security there will not save more lives at public places overall. The security will simply displace the risk and raise the cost of travel.
Worried travelers might keep in mind that worldwide, there are about 2 billion passenger boardings and arrivals a year, and nearly 20 billion since 9/11. About one out of 130 million people have died at the hands of terrorists on airplanes or at airports. The odds are slender, though any toll is a tragedy.
The opinions expressed in this commentary are solely those of Brian Michael Jenkins.