MOSCOW — Mikhail Gorbachev made one last stab at keeping some sort of Soviet-like Union alive. After the failed coup of August 1991 had led to the suspension of the Communist Party and the emergence of the various republics as the true centers of power — with Boris Yeltsin’s Russia taking the conspicuous lead — Gorbachev still hoped to knot together a confederation.

The three Baltic republics were gone — fully independent — but a successor to the U.S.S.R. could manage without them. There were still 12 other republics. Gorbachev envisioned an economic union, a sort of Soviet Common Market. The idea seemed to get some traction, and a signing date for a new treaty was set. This was at least the third treaty Gorbachev had sponsored that year; the first two had fallen by the wayside, overtaken by events.

On Oct. 17, the day before the signing, Ukraine had second thoughts and pulled out. Ukraine was experiencing an upsurge in nationalist feeling, particularly in its western provinces, but more generally Ukrainians were tired of running their economy to fulfill Moscow’s orders. And their economy was in tatters: A visitor to a monastery in Odessa that fall found the monks forced to wear brown robes, because black cloth was unobtainable. Ukrainian leaders said they worried that Gorbachev’s economic union would lead to more of the same.