Today's state funeral for Ronald Reagan surely demands the extraordinary measures that have been taken to protect against a terrorist attack.

But the past week has also offered reminders to visitors and residents of how much the everyday security measures have altered the life of the city. Access to public places has been significantly curtailed. The public landscape and streetscape have been scarred, in some cases permanently. And the economic costs are measured not only in out-of-pocket security costs, but in lost productivity for workers and a diminished experience for visitors.

After Sept. 11, 2001, much of this was inevitable, and the potential threats are considerable. But it seems we have reached a fork in the road. Either we are going to decide that, having made reasonable accommodations, we are willing to live with a certain level of unmitigated risk in order to preserve the Washington experience, or we're going to go to the next level and accept the reality of living and working in a semi-permanent war zone.

I suspect, for example, that most Americans would be surprised to learn that they can't walk those stairs on the west front of the Capitol that they saw on television Wednesday evening. Nor can they picnic on the Capitol grounds, wander the ornate corridors of the Capitol or catch a glimpse of Sen. John McCain (R-Ariz.) while riding the Senate subway. In the experience now envisioned by the Architect of the Capitol, visitors will be herded into a new underground center for a virtual tour, followed by a guided group visit to the Rotunda, Statuary Hall and the old Supreme Court chambers.

The White House, meanwhile, has been turned into a fortress. Ordinary citizens are no longer allowed to tour the public rooms or even the spring gardens, and the Bush family is discouraged from venturing out into the city. The debate about reopening Pennsylvania Avenue or E Street is long since over -- the question now is whether to close Lafayette Park and restrict vehicles on 17th and H streets.

Down on the Mall, it was only the push-back from the National Capital Planning Committee and the Fine Arts Commission that prevented the Washington Monument from being turned into Fort Washington. We can only imagine what the Park Service has in mind once they turn their attention to the Lincoln and Jefferson memorials.

Washington has a long and proud tradition of accommodating parades and marches into its busy schedule. But now that most of these are considered "security events," officials think nothing of ordering entire buildings evacuated or giving tens of thousands of workers the day off.

It's easy to understand how this mission creep happens. Security officials genuinely want to do a good job, and there's little political or bureaucratic pressure on them to give much weight to social and economic costs. In the past, business leaders and District officials have tried to get the security types to strike a better balance, but having been ignored so often, most have now given up.

How much worse can it get? Just ask the folks up in Boston, who now rue the day they won the prize of hosting this year's Democratic convention. Security officials have ordered the main highway through the city closed for the entire convention week because it passes near the convention hall. Ditto all commuter trains from the north and west that arrive next door at North Station. In response, many businesses have announced they will close for the week, while commuters are being urged to stay away. And what was supposed to be a bonanza is now shaping up to be a political and economic disaster.

Don't get me wrong -- striking the right balance between security and other interests is devilishly hard. No official wants to be the one facing the next 9/11 commission explaining why he didn't erect one more barrier or impose one more restriction.

But I do know what will happen if we never debate these issues openly and simply defer to the judgment of security officials. Just as war is too important to leave to the generals, homeland security is too important to leave to the cops and terrorism experts.

Steven Pearlstein can be reached at pearlsteins@washpost.com.