IT has been a tough summer for those of us in the field of Soviet security studies. First, the August coup swept away the ruling Communist Party, shattered the Soviet armed forces, and cast doubt on the very existence of the country itself. Then, on Sept. 27, the other half of what we learned in graduate school wasn't true anymore, either.It's not enough that Mikhail Gorbachev spent six years undoing all that we had learned about Kremlin intrigues, party purges, and the Politburo's lineup at May Day parades. In one brief speech, President Bush scrapped most of the nuclear weapons that many of us spent years trying to understand. Now, we weren't utterly inflexible. Indeed, I entered the field of United States-Soviet relations more or less with Gorbachev. I understood early on that he was a moving target and would require all the attention and intellect I could muster. At Geneva or Reykjavik, he was certainly nimble, fascinating, at times even entertaining. But it was nothing we couldn't handle within the traditional analytical paradigm of your standard single-party totalitarian empire. True, some longstanding assumptions about irreversible Soviet expansionism and thirst for military power wavered when Gorbachev agreed to ban intermediate missiles from Europe. They wavered a little more when Soviet troops marched out of Afghanistan. But Russian history is punctuated with brief periods of retrenchment and consolidation. This was still essentially the same country our professors had taught us about. The democratic revolutions of Eastern Europe, the collapse of the Berlin Wall and, above all, Moscow's willingness to stand idly by sent a deep chill through the analytic community. Countless dissertations and book manuscripts on European security, mobilization on the Central Front, or - get this - East German military doctrine were throttled in their intellectual cradles. Those of us fortunate enough to have avoided such scholarly catastrophes clung to the basic assumption that the Soviet Union remained the largest power on the continent with the largest army and the largest nuclear arsenal. Contested elections, a rambunctious press, and Boris Yeltsin notwithstanding, the place was still run by communists. Even so, we did adjust. I slowly became convinced that the Communist Party was losing control to the dozens of new nationalist movements claiming some right of self-determination. Even as I gazed wistfully at the shelves of books that explored the history and politics of the old union, it seemed less and less likely that the old monolith could hold. That is not to say that there wasn't a warm glimmer of familiarity in August as I watched the tragicomic press conference staged by the coup plotters. In the absence of harder information, there reawakened a long-dormant reflex to draw meaning from their seating arrangement. When the coup crumbled, of course, the communists and the country itself dissolved as well. I tried to put a brave face on in it all for my parents, who had financed so much of my now tattered education, and for my friends who gently shared their concerns about career prospects in a field that no longer existed. I would mutter something about how it was still a dangerous world out there, and how any country with all those missiles pointed my way would still have my attention. Privately, I consoled myself that at least I didn't know any less about the Soviet Union than anyone else. Besides, if all my Soviet learning was obsolete, then at least my studies of defense and security policy would see me through. Then Bush dropped the other shoe. From Berkeley to Cambridge, degrees have been earned and professorships secured with ruminations on the value of "extended deterrence," the wisdom of no-first-use doctrines, and the importance of missile throw-weight. Whole forests have died for published diatribes on the existence of a window of vulnerability, the difference between offensive and defensive forces, and the morality of mutually assured destruction. There were SALT, START, and SDI, ICBMs and SLBMs, diads a nd triads. It was another time; a simpler time. Alas.... Sure, the collapse of Soviet communism and the liquidation of nuclear arsenals may well serve the cause of world peace. And sure, world peace was distantly the cause I intended to serve when I first bought all those books and began to read them. It's just that most of us would like more than a few weeks for so many years of study to be rendered obsolete. Most of us would have liked a little more time to adjust to the cruel reality that we had better start learning some German.