JUST when it seems glasnost can't go a step further, it does. The ongoing public criticism in Russia of V.I. Lenin shatters yet another seemingly impossible barrier in the Soviet Union.
In the past year, official history in Russia has undergone a remarkable change. Mikhail Gorbachev wants ``the blank spots'' of the past filled in. Trotsky has gone through a minor rehabilitation. Stalin's personal killing fields in the forest of Kurapaty near Minsk, site of more than 100,000 deaths, are openly discussed - as is the secret Nazi-Soviet pact allowing Stalin to annex the Baltic states.
Yet the ability to criticize Lenin, supreme patriarch of the Soviet state, has been held out as the litmus test for the seriousness of glasnost. And Lenin is now under some attack in literary journals.
A 1963 novel ``Forever Flowing,'' by Vasily Grossman, has been published - portraying Lenin as a cunning and ruthless tyrant, instead of a magnanimous and kindly figure. On TV last month, two leading intellectuals discussed interring Lenin's body, now on display in Red Square. This was unthinkable even 18 months ago.
A shift in attitude is underway. Soviet officials realize they have to be more realistic in their statements. Cynicism about communism and the party line is widespread among Russians.
The main question now is: How will this phase of glasnost be managed? Changing history, which influences the way a people identify themselves, can be explosive.
For Russians wanting Western-style freedoms, the Lenin critique provides ammunition for change.
Hardliners, on the other hand, will use the heretical tainting of Lenin against Gorbachev.
Gorbachev's own ministers of ideology are likely to go one better. The failings of Lenin, questioning his means, showing his weaknesses, can be used to make Lenin more, not less, of a state hero. He may emerge stronger. He can be presented as a fallible human battling titanic forces - a model for today. This ``warts and all'' policy is now being used successfully with the shortcomings of the Soviet space program.
(Gorbachev needs Lenin for the socialist democracy on which he lectured French intellectuals.)
Russians today generally know when they are being propagandized. Hence, propaganda has to be more subtle. Authority must be asserted more indirectly. Lenin worship, however, is still strong among Russians; the ability to play on it shouldn't be underestimated.
Some have suggested that the real test of glasnost will come when the Soviets are honest about the stifling of democracy in 1918 by Leninist Bolsheviks who didn't allow Kerensky's freely elected provisional government to rule. Perhaps - though Kerensky had warts too, including an imperial claim on Finland and the Baltic States.
Maybe the real test of glasnost isn't openness about the Soviet Union, but greater openness about democracy in the West. Say, an honest appraisal of American history in Soviet schools.
But Gorbachev isn't ready to embrace John Adams, Thomas Jefferson, or Abraham Lincoln, yet. For now, he still needs Lenin.