What greater luck can a journalist have than to be present at the scene when, in a transformative moment, the world changes?</p><p> Eighteen summers ago, the summer of 1991, I had such good fortune.</p><p> We had spent that season &mdash; 12 of us, eight Americans and four Russians &mdash; on a 2,700-mile expedition that traversed the length of the most splendid, most pristine, of Russia&rsquo;s great rivers, the Lena.</p><p> Beginning at its source in the mountains above Lake Baikal, our route lay northward &mdash; first by rafts in the upper canyon, then canoes, and finally by boats of ascending size &mdash; until we reached the Lena&rsquo;s mouth at the coast of the Arctic Ocean.</p><p> Along the way, we saw evidence of the brutal history of forced labor, remnants of the infamous <em>gulags</em>, and scenes of desperate need in settlements huddled on the banks of that great stream.</p><p> We heard Siberians &mdash; both ethnic Russians and indigenous native peoples &mdash; speak their bitter resentment of a Soviet system that they believed had plundered their region and cheated them of their hopes.</p><p> Our principal companions were geographers with the Siberian branch of the Soviet Academy of Sciences. Victor, leader of the Russian team and the one without whose courage and resourcefulness our undertaking almost surely would have failed, was 38. Valera, his longtime friend, was 37, and Volodya, the youngest, 32.</p><p> Setting off in June, we reached the shore of the polar sea in an August snowstorm. The arctic season had turned.</p><p> We camped some days there on the coast, cooking potatoes in the fire, talking long into the nights, drinking a little of that clear fluid the Russians make so well, not wanting to let go of the experience we&rsquo;d shared.</p><p> By journey&rsquo;s end we had come to love those men as brothers. One of them, looking at me through the firelight, said, &ldquo;The tragedy is that we&rdquo; &mdash; meaning Russians and Americans &mdash; &ldquo;have been lied to for so long about each other.&rdquo;</p><p> On Aug. 18, our American crew flew from Tiksi, a Soviet arctic air base, back to Moscow. And we woke the next morning to the historic event &mdash; the attempted coup by hard-liners &mdash; whose failure resulted in the end of communist rule and the collapse of the Soviet empire.</p><p> This coming Wednesday will mark the 18th anniversary of that significant day &mdash; a day when the world truly did change. The Iron Curtain was dismantled, and long-captive Soviet European and Asian satellites reclaimed their independence.</p><p> After most of a half century of hostility and the risk of nuclear confrontation, the texture of relations between the world&rsquo;s two superpowers was characterized by new possibilities of civility and cooperation.</p><p> &ldquo;For us in Siberia,&rdquo; Victor wrote in a letter, &ldquo;times are hard and they are sure to get harder.&rdquo; The ruble had lost its value. The scientific institute that employed him and our other expedition partners was without funds even to pay its staff.</p><p> And there was little likelihood that Siberians would experience much loosening of Moscow&rsquo;s fist. For their region is a treasure lode of resources whose continued exploitation is essential to the economic future of the Russian Republic, all that remains of the empire.</p><p> Across these nearly two intervening decades, I have found myself thinking more often lately of those Siberian friends with whom we shared that grand adventure.</p><p> Victor and Valera would be getting on toward 60 now. Volodya would be 50. The younger of Victor&rsquo;s two sons, Nikita, would be in his 20s; the older, Alyosha, past 30. How have the years treated them and their families? What further shapes have their lives taken?</p><p> I would like very much to know, to share memories of our weeks on that great river, to look once more into the transparent depths of Lake Baikal and see again the forested shoulders of the mountains in whose basin that glorious lake lies.</p><p> They, and all of that, were part of an experience so singular as never to be repeated. And about which I feel, as I did when we were camped there on the Arctic coast, that I cannot bear to let it go.</p><p> I looked yesterday at the possibilities of air travel to Irkutsk. The cost would be serious, and the time away from work a problem. And yet&ensp;&hellip;</p><p> Maybe it will happen.