WHEN SEN. JOHN W. Warner raised his voice recently in opposition to the Pentagon's proposed transfer of thousands of Northern Virginia defense workers, he recast what had until then looked like parochial squawking about local job loss and dislocation. For Mr. Warner -- Virginia's senior senator, Republican chairman of the Senate Armed Services Committee, a former secretary of the Navy -- is not only one of the most influential members of Congress on military matters; he's also the author of the very legislation that established the Defense Department's procedures on base closings and facility reshuffles. When Mr. Warner says the Pentagon bent the rules, he's worth listening to. He wrote them.

At issue is the Defense Department's attempt to vacate millions of square feet of leased office space in Northern Virginia as part of its overall proposal to eliminate 180 military installations nationwide. The Pentagon defends its proposal to relocate agencies housed in leased buildings, most of them in Arlington, on the grounds of a new security rule requiring structures to be set back 82 feet from the road as a precaution against truck bombs and other terrorist attacks. Better to house the agencies on military bases, where they can be protected, the Pentagon figures. Mr. Warner contends that the Pentagon ignores the chief criterion laid out in the law governing base closings -- namely, that "military value" be the guiding principle for such decisions. By setting a goal of vacating leased office space near Washington, the Pentagon spurned the language of the legislation and congressional intent. "This is not permitted by law," Mr. Warner said.

In addition, we wonder about the logic of moving a hodgepodge of relatively obscure defense agencies to secure locations -- at significant expense and upheaval -- while leaving other government offices, including those engaged in sensitive missions, in more exposed buildings.

The base-closing process merits support; it rightly insulates sensitive decisions from parochial political pressure. Still, there are sound reasons even beyond Mr. Warner's critique to subject the Pentagon's proposals to stringent review, as the nine-member Defense Base Closure and Realignment Commission is doing. It will present its final list of targeted bases Sept. 8 -- a list that President Bush and Congress must accept or reject in full. One is that some or many highly specialized defense workers in Northern Virginia, including those with security clearances, may refuse to relocate if their agencies are moved. Rather than subject themselves to long commutes, they say they will simply switch to private-sector jobs with defense contractors or consultants. That is a risk worth taking seriously, as testimony to the base commission underlined last week. A. Fenner Milton, director of the Army's night vision laboratory, warned that the proposed move from the lab's current location in Arlington to Aberdeen Proving Ground -- on the Chesapeake Bay northeast of Baltimore -- could devastate his lab by stripping it of irreplaceable scientists and technology managers who would easily find other jobs in the Washington area.

Another risk is that the Pentagon's proposed shifts would break up a critical mass of defense researchers, scientists and technology managers whose current proximity in Arlington is said to be a breeding ground of creative synergy. The Pentagon, the Army, the Navy and the Air Force all have advanced research agencies there, close to the National Science Foundation's headquarters. Virginia officials have proposed that even if the base commission endorses most of the Pentagon's other recommendations, it should allow those research agencies -- representing about 2,000 jobs of the 20,000 that would be eliminated in the close-in Virginia suburbs -- to remain in Arlington, in one of two sites identified by local officials that meet the Pentagon's setback requirements. That seems an idea worth considering.