A number of recent decisions concerning national security may be making us less safe against terrorist attack. We may be over-investing in one area while ignoring the real threat in another.

For example, the most recent round of proposed base realignments and closures could put thousands of people in harm's way. Based on current accident and fatality rates, the proposed realignments and closures could lead to the death of 27 people annually by 2010 and 50 annually by 2020.

These startling figures derive from a comparison of the Metropolitan Washington Council of Governments' recent estimate of increased miles traveled to reach new base locations -- 74,000 new miles a day -- with National Highway Traffic Safety statistics for the average highway accident fatality rate per million miles traveled (1.5 deaths). By relocating employees to more secure facilities in the region, the government might actually increase the incidence of injuries and fatalities.

Too often our response to terrorists has been tailored to the last attack, not to the attack that might come next. For an example, look no further than the disparity between the $18 billion spent for airport security post-Sept. 11, 2001, and the debate in Congress over whether to spend the same amount on transit security that was spent last year -- $250 million -- or less than last year. This debate still rages even after the two recent terrorist attacks on the London transit system.

We need to focus on investments that aren't simply palliative. We need to ask tough questions about risk and return. That may mean investing more in redundancy and capacity to lessen the effect of an attack and to deal better with the aftermath. Regrettably, so far the focus has been almost entirely on avoidance, and that doesn't appear to be changing. The recent realignment of the Department of Homeland Security reinforced this by eliminating the assistant secretary for infrastructure protection.

Homeland security investments could be good for the economy while making us safer if we made targeted investments in areas such as rerouting rail traffic away from the center cities that they do not serve. These investments could improve both security and our international economic competitiveness by eliminating choke points, increasing efficiency and replacing aging, unreliable infrastructure. Unlike most other homeland defense investments to date, rerouting could reduce transportation delay and costs.

Our bridges, highways and roads need to be kept at peak condition for emergency situations. Right now two critical links connecting the District, Maryland, Virginia and national defense assets such as Andrews Air Force Base lie rusting and decaying. The 11th Street and South Capitol Street bridges need the kind of funding that the delayed highway bill could provide.

The administration of Mayor Anthony A. Williams has promised to set aside half the District's off-street parking taxes to pay for a new 11th Street Bridge. It also has invested in the Metro Matters program, which protects infrastructure through improved maintenance and contributes to the acquisition of more rail cars. But the limited resources of states and cities are not enough.

According to an old saying, we never seem to have enough time or money to do things right, but we always have enough of both to do them twice. Congress and the administration need to know that they are looking at a second chance.

Will they get it right this time?

-- Dan Tangherlini

is director of the D.C.

Department of Transportation.