AS radical reform shifts into high gear, Russian unemployment lines will include plenty of former KGB agents. Yegor Yakovlev, until recently editor of the liberal Moscow News and now head of the state broadcast system, has announced that secret police officers assigned to his agency are out of a job. KGB offices in the Baltics are packing up, and many border guards detailed from headquarters in Moscow's Lyubyanka Prison will probably be cashiered.The rapid crumbling of the surveillance mechanism erected by V. I. Lenin and his lieutenant, Felix Dzerzhinsky, indicates that perestroika and glasnost had long since eroded its foundations. As in the Red Army, fault lines of dissent had opened in the KGB. Its ranks have even produced a few outspoken critics of the Leninist system, such as parliamentary deputy Oleg Kalugin, a former KGB "general" who is now taking a hand in dismantling the agency. The most remarkable aspect of the past two weeks has been the transformation of the citizenry - from people cowed by fear of state power to people not afraid to take to the streets and express themselves openly. In the past, the KGB's network of informers and enforcers would have pinched out any hint of popular politics. Now the network is tattered by defections and confusion - but most of all by a populace that despises its onetime tormentors. The toppling of Dzerzhinsky's statue in front of Lyubyanka w as one of the first acts of the jubilant crowds after the coup collapsed. But the KGB has a staff of 700,000, embracing bureaucrats, spies, and paratroops. Its files are crammed with the names of thousands of citizens who either collaborated or were targets. Taking this structure apart - reassigning the KGB troops, eliminating many functions, and remolding others into a scaled-down foreign-intelligence operation - will take time. Should the demolition include public inspection of the KGB's files? Concerns about witch hunting and vengeance argue for keeping the files closed, and new KGB chief Vadim Bakatin has decided that information about informers will not be made public. The informer system, however, will be firmly shut down, according to Mr. Bakatin. The peoples of a rapidly fragmenting Soviet Union are immersed in the task of defining what freedom will mean for them. That work has to include keeping a close watch on what remains of an organization that watched them for 70 years.