Inspired by the success of Poland's Solidarity trade union, nationalists in the Soviet republic of Estonia are planning brief strikes to protest food shortages and political oppression.
''People assumed that nothing could be changed in the Soviet empire,'' one source said. ''But they have heard, through Western radio reports . . . what strides have been made. And now it does not seem so impossible.''
The protest groups, who claim the Soviets illegally occupy Estonia, are calling on people to stop work and refuse to use public transport for a half hour on the first day of each month beginning Dec. 1.