The price of insecurity

Madrid was not hosting a national political convention when the bombs went off.

It was a workday morning like any other until some explosive-laden backpacks tore apart four commuter trains last March, killing 191 passengers and wounding many hundreds more. It was not unlike the day two and a half years before when thousands of Americans died sitting at their desks or on airliners that had been turned into guided missiles.

The routine nature of those days, the very ordinariness of those victims is worth remembering as we suspend common sense and civil liberty for a sense of security that cannot be bought, even for $50 million, the amount being spent to protect the Democratic National Convention in Boston next month.

This is what an arms race looks like in the War on Terror: concrete barriers, police overtime, road closures, canceled trains, restricted air space, baggage searches, and bomb sniffing dogs. These measures are not a coordinated response to an actual threat; they are an expensive salve for an inherent fear.

There have been no specific threats against Boston, where Democrats will meet July 26-29 to nominate Massachusetts Senator John F. Kerry for president, or against New York, where Republicans will reaffirm their faith in President George W. Bush a month later. There has been, instead, an unquestioned assumption that the conventions would be an appealing, symbolic target of opportunity for terrorists.

Why? If surprise and vulnerability are crucial weapons in the terrorists' arsenal, why attack a fortress when the guards are on alert? Maybe, like the nuclear arms race before it, this kind of massive security buildup is designed to act as a deterrent: If the evildoers know we are ready for them, they will not come. The problem with that rationale is the question that logically follows: When and where does the security escalation stop?

The Boston transit system will be the first in the nation to conduct random searches of passengers on subway and commuter rail lines. The Massachusetts Bay Transportation Authority will prohibit riders from carrying any bag larger than a briefcase and, without the nuisance of probable cause, passengers will be denied access to public transit stations if they fail to comply.

If encroachments on constitutional protections against unreasonable search and seizure are necessary for public safety while the Democrats are here, why won't they be needed when the delegates go home? Why confine baggage searches and carry-on restrictions on the city's transit system to the four days the Democrats are in town? Why limit random searches to public transit? Why not set up roadblocks at every bridge and tunnel entrance to ensure that no suicide bomber attempts to take out the Zakim Bridge or the Ted Williams Tunnel?

It is a false dichotomy to argue that we must choose between safety and liberty. Additional security measures are obviously a wise investment in these volatile times, but there is more than a hint of hysteria in the preparations for the Democratic Convention. There is an unwillingness to acknowledge how much we cannot control and how much we can lose if we surrender to fear.

After a rash of school shootings in the 1990s, school administrators across the country grasped at straws to keep their students safe. They banned black trench coats, mandated the use of clear plastic backpacks and installed surveillance equipment. It made them feel that at least they were doing "something," no matter how ineffective.

Part of the "something" that school administrators were doing then and that convention planners are doing now is eroding what it means to live in a free and an open society. The tradeoff is supposed to be a sense of security, but as commuters in Madrid learned on an ordinary day last March, safety from the shadowy strikes of terrorists cannot be bought, even for $50 million.

Eileen McNamara is a Globe columnist. She can be reached at mcnamara@globe.com.