The Union Club Mysteries by Isaac Asimov

me. Throughout his dozen years of service for the Department, however, Archie was never without something to do.
    Does it occur to you gentlemen that there are well over a hundred foreign embassies and an even larger number of consulates in the United States?
    Every single one of them must gather information that is of service to their nation, as our embassies and consulates do abroad in the service of our nation. Information gathering must be carried out more or less clandestinely and, in the case of a number of embassies, illegally, and for purposes that menace the security of our country.
    Furthermore, the internal political battles of various nations are fought out on the territory of the United States. Various terrorist groups, or dissidents, or freedom fighters (they're called different things, according to viewpoint) operate here.
    All these things must engage our attention and Archie was an excellent worker: unobtrusive, skilled and persuasive.
    That he be persuasive was important, for one of the tasks of any skilled agent is that he manage to gain the confidence of someone on the other side. Someone working for the enemy is clearly a particularly reliable source of information, whether he is a defector on principle, a greedy fellow in search of money or other rewards, or simply an overconfident blabbermouth. Naturally, a defector on principle is the most reliable source and the one most likely to take large risks.
    There was no one like Archie for finding the enemy who would work with us out of conviction and, at the time under discussion, he had one. We knew none of the details, of course, but the Department was pretty sure he had one. It was the easiest way of accounting for the nature and reliability of the information he fed us. ' Nor did we try to find out what his source was. It makes sense not to do so.
    When one has a spy in the enemy camp, the fewer who know his identity, the safer the spy and the connection. Even if the agent were to communicate the identity to a thoroughly reliable co-worker, the communication itself would be a point of weakness. Messages can be intercepted and interpreted, words overheard, gestures understood. The behavior of two people can serve as a more reliable lead for enemy eyes, than the behavior of one, the behavior of three still more so, and so on.
    It is best, then, if there is a thin line between agent and enemy informer, a very thin line. If only the agent knows the informer, that is best. The informer himself feels more secure if he is confident that only one person knows what he is doing. He will then speak more freely. Archie had the ability to inspire that kind of confidence and he could do so because he had the conscious knowledge that he never double-crossed.
    It was a very special loss to us when Archie was killed.
    There was no way of telling that he had been killed in the line of duty. No one left a calling card. He was merely found dead in a doorway in a dubious street of one of our large eastern cities.
    He had been knifed, and the knife had been withdrawn and was gone. His wallet was also gone, and it might be taken for granted that it was an ordinary mugging.
    That is what the local police took it for, at any rate. Archie was not a well-known person; he had a professional unobtrusiveness and his cover was that of a clerk in a liquor store, so there was no reason for the police to give it special attention or for the press to stir much.
    Nor could the Department take a very active interest. In the first place, we didn't find out about it till well after the fact. In the second, it would have been counterproductive to adopt too high a profile in the matter.
    The killing might conceivably have been an ordinary mugging with no connection whatever to Archie's work. In that case, it would certainly be a bad move to allow anyone watching the Department (and of course we are under surveillance by dozens of groups of undesirables) to learn, definitely, that Archie was an