Can Beijing's subway stations be made safe against suicide terrorist bombing attacks? Last month's pair of blasts in crowded Moscow subway stations, which killed scores of commuters, has naturally focused attention on this question.

Of course, subway security was tightened in the run-up to the 2008 Olympic Games, when passengers had their bags screened before entering train platforms. These checks, which remained in place after the Olympics, have made certain kinds of terrorist attacks next to impossible to carry out.

These include the March 2004 Madrid rail bombing, which was carried out by an Al-Qaida inspired terrorist cell and killed 191 people while wounding another 1,800. The same can be said for the March 1995 Aum Shinrikyo Sarin Gas attack against the Tokyo subway.

Unlike the Moscow bombings, these attacks were not the work of suicide bombers. They were instead carried out by terrorists who smuggled explosives and poison on to trains and subway platforms. The rigorous baggage screening in Beijing's subway stations would certainly prevent such incidents.

However, suicide bombers present special security problems. Since they strap explosives on to their bodies, baggage screening provides no defense against this type of terrorist attack.

One defense against suicide bombers is random police patrols in subway stations.

In the wake of the Moscow tragedy, police officers, accompanied by patrol dogs, have appeared in some heavily-used Beijing subway stations during peak hours.

This police presence could give potential suicide bombers cold feet, causing them to give themselves away through nervous behavior or abort their missions. Unfortunately, Beijing's subway system now has lots of stations and, as new lines open up, will soon have even more. All are crowded during rush hour, and the police can't be everywhere at once.

It is also neither practical nor effective to conduct random or targeted body searches of subway commuters to catch potential suicide bombers. Random searches are by nature rare searches, so a suicide bomber could easily slip through this line of defense.

Nor is it fair to target specific groups, as the US did to Arabs in the wake of Sept 11.

The only real effective defense would be to subject subway commuters to the kind of screening given to airline passengers. But the huge numbers of people who take the subway makes doing that impossible. Moreover, as the cases of the shoe bomber, Richard Reid, and the underwear bomber, Farok Abdumutallab, illustrate, such checks are not 100 percent effective.

So the bad news is that there is no foolproof way of stopping a really determined suicide bomber from doing a Moscow-like attack on one of Beijing's subway stations. However, the good news is that such attacks are by definition very rare. They are difficult to organize and plan and it takes time and effort to recruit and train suicide bombers.

To be sure, even very infrequent terrorist attacks that kill and seriously wound large numbers of subway commuters are tragic events. But the chances of a Beijing subway commuter losing his/her life to terrorist bombings are on a par with being struck and killed by lightening.

In fact, over 100,000 people die every year in traffic accidents on China's roads and highways.

Even with the heightened risk of suicide terrorist bombings, taking the subway is far less dangerous than driving in the capital.

Finally, there is good reason to believe that terrorist groups might think twice before attacking crowded transit points. Since many innocent civilians would be killed, these actions would cause the Chinese people, who are already quite patriotic and supportive of their national government, to understandably rally around their leaders.

While terrorists are vicious and amoral people, they are not completely stupid. Many know that targeting civilians is always counterproductive. And recent news reports indicate that some Chechen separatist leaders have privately condemned the Moscow attack.

Indeed, notwithstanding the overheated rhetoric about the terrorist threat, recent history shows that modern, well-organized and functioning states always have the upper hand in dealing with terrorist groups.

During the 1970s, the German red army faction, Italian red brigades, and Japanese red army were all quickly crushed, while Britain learned to live with decades of repeated IRA bombings. At the end of the day, even the IRA concluded negotiating was better than bombing.

So I'll keep my fingers crossed and continue using the subway to get around Beijing.

And even a devastating terrorist suicide bombing - this assumes that I'm not in harms way - won't change this behavior. I expect that Beijingers, who are tough and resilient people, will do likewise.