E. Germans Put Hard-Line Regimes on Notice

THE communist bloc in Eastern Europe is no more. That fact is for sure, after all that has happened in East Germany, its keystone. The bloc's hard-line remnants, still defying change, are seriously isolated and on the defensive.

Until a month ago, of four neo-Stalinist regimes, the German Democratic Republic looked least likely to bow to perestroika (restructuring), even after that first surge of its citizens through Hungary's open border to the West.

But at that time only a few perceived that what was happening in Hungary itself and in Poland presented a bigger threat to the hard-line countries than anything that had happened in Eastern Europe before.

East Germany was the first to succumb to this gale of change. In a matter of weeks, 40 years of history were swept aside - and most amazingly of all, the Berlin Wall with it.

One may write off the Iron Curtain, too. Bulgaria made its own crack in what is left of the curtain by throwing out Todor Zhivkov. He was Eastern Europe's last surviving prot'eg'e of former Soviet leader Leonid Brezhnev.

But even with a younger, apparently more imaginative leader, this change doesn't necessarily mean Bulgaria is on the road to democracy. What it does mean is that the last two hard-liners, Czechoslovakia and Romania, are so isolated that it is a very open question how long they can contrive to stay immune to reform. But the pressures of what is happening elsewhere are implicit from Czechoslovakia's decision announced Tuesday to permit a freedom of travel (to the West now, as well as East) that its people have not enjoyed since 1968. If leaders in Czechoslovakia and Romania were already aghast at the ``antisocialist'' developments in Hungary and Poland, East Germany must have sounded like the last trump.

Visiting Austria recently, Ladslav Adamec, the Czechoslovak prime minister, spoke of ``positive elements'' in Alexander Dubcek's 1968 Action Program. He even hinted at ``partial reevaluation'' of the Prague Spring reform movement. But no more will be heard of that just now, since the Communist Party establishment's claim to authority resides in the ``normalization'' since 1968. Cautious economic restructuring, possibly, but no democratic reform will be Prague's watchword with increasing emphasis now. Nicolae Ceausescu of Romania - the last old defender of arch-conservatism still in power - totally dismisses the need for reform. ``Our system,'' he said, ``is not negotiable.''

Nonetheless, leaders in Prague and Bucharest are encountering growing internal unrest, which is ever more open in Czechoslovakia and is beginning to break through the surface in Romania.

A recent report spoke of a strong anti-Ceausescu front within the party calling outright for his removal. It could well be so. Earlier this year, six formerly high-ranking party officials (three had been Politburo members) smuggled to the West the text of a detailed declaration condemning Mr. Ceausescu's dictatorship, disregard of human rights, and economic mismanagement.

His unopposed reelection at the party congress Nov. 20-25 is already cut and dried, following a recent Central Committee resolution. But, with all the mounting pressures from outside, a challenge is not out of the question.

Meantime, it is worth recalling that not so long ago East Germany could boast the soundest economic standing in the bloc. It prompts an intriguing thought. With the native German tradition for discipline and hard work and with its economic muscle flexed again with West German help, it is not at all beyond possibility the East Germans - before the Soviets, the Hungarians, or the Poles - will manage to make perestroika work.