The argument that Mr. Pollard did no harm to the United States echoes his own claim at his sentencing hearing. There, the judge stopped him and pulled out Secretary of Defense Caspar W. Weinberger’s affidavit. He asked Mr. Pollard to explain a section noting the disclosure of one particular document — the Top Secret Radio Signal Notations Manual. The manual listed the physical parameters of every known electronic signal, noted how America collected signals around the world, and listed all the known communications links then used by the Soviet Union. It would permit any recipient to take measures to avoid the United States’ collection of signals and communications intelligence information, and we have no idea how widely this might have been shared. Both during the Cold War and in counterterrorism today, intercepting enemy communication is vital; disclosing our methods is an even greater danger than releasing what we have collected.

Other defenders of Mr. Pollard believe that he never gave information that wasn’t already supposed to be shared with Israel. But he sold the daily report from the U.S. Navy’s Sixth Fleet Ocean Surveillance Information Facility in Rota, Spain — a top-secret document filed every morning at the time reporting all activity in the Middle East during the previous 24 hours. These were so important that, when Mr. Pollard missed stealing some of them, his Israeli handlers were upset.

Finally, there is the defense that he gave information only to an ally. This assumes that all allies are entitled to full disclosure on everything, which is a dangerous idea. As Benjamin Franklin put it, three can keep a secret if two of them are dead. This claim also assumes that Mr. Pollard dealt only with Israel, when in fact he attempted to deal with multiple countries and even disclosed classified information to a South African defense attaché.

We will never know the full extent of the damage caused by Mr. Pollard. The Israelis returned to the United States a paltry few thousand documents, which they claimed was all that they had received. However, Mr. Pollard confessed in a debriefing that he had turned over enough documents to occupy 360 cubic feet. The quantity was so vast that his handlers rented an apartment and installed high-speed copy machines.

In 2001, Seymour Hersh reported that William J. Casey, the former director of central intelligence, charged that information relayed by Mr. Pollard had been traded to Russia for Jewish émigrés. Others, including a former director of naval intelligence, have expressed concern about information passed to Israel having ended up in Soviet hands.

At the time of Mr. Pollard’s sentencing, federal law did not permit the death penalty, and a life sentence meant a maximum of 30 years. As such, Mr. Pollard is close to release, counting time off for good behavior. That release, however, should occur when his sentence expires and not, as four former directors of naval intelligence have put it, as a result of a “clever public relations campaign.” Mr. Pollard has never expressed regret or admitted to harming America’s national security, and he has not applied for parole even though he is eligible. He has done his crime. Let him do his time.

M.E. Bowman is a former deputy general counsel for national security law at the F.B.I. and a former deputy of the U.S. Office of the National Counterintelligence Executive.