DESPITE THE threat level being downgraded from orange to yellow, U.S. Capitol Police Chief Terrance W. Gainer has once again surrounded the Capitol complex with his "pop-up checkpoints," as D.C. Del. Eleanor Holmes Norton (D) calls them. Mr. Gainer's fascination with military-type security that bears no relationship to threats of terrorism or to intelligence warnings might be dismissed as a personal predilection were it not for the fact that his preferences have dramatic ramifications for the nation's capital, of which his Capitol Hill domain is only a small part. Everyone else involved in protecting the city, from D.C. Police Chief Charles H. Ramsey to a host of federal officials, not to speak of the traveling public, understands the problems caused by checkpoints that are arbitrarily imposed with no consultation and little notice. How and why that simple point seems to be lost on Mr. Gainer is a mystery congressional leaders must solve. In the meantime, some semblance of sanity about security needs restoration downtown.

In the name of public safety, Washington is slowly disappearing. A few months ago, The Post reported on the closing to citizens of the steps and terraces on the west side of the Capitol. Concrete barriers stand as silent sentinels between people and their national shrines. Whole sidewalks and streets have been sacrificed with no thought given to traffic congestion, the needs of emergency vehicles or the loss of evacuation routes. District residents and their leaders are left out of the loop as their city is changed, block by block, before their eyes. What's happening in the city may serve some special interests, but the denial of public access is not in the national interest.

Ms. Norton has asked congressional and District security officials to start holding monthly coordination meetings, something that they apparently had agreed to do in August but that never happened. That would be an excellent forum in which to develop a citywide security plan. It could also serve as the proper setting in which to vet and bring within the range of reason those renegade security plans so beloved on Capitol Hill and in the recesses of nonconforming federal agencies. Nothing less than the life and vitality of the nation's capital for millions of residents, visitors and commuters is at stake.