With their storm-trooper boots planted firmly in the grass of the Washington Monument grounds,about three dozen swastika-festoomed members of the National Socialist White People's Party held a rally yesterday to denounce blacks. Jews Puerto Elicans, Mexicans, Asians and just about everybody else who cannot be classified as an Aryan white.

A small and apparently incredulous audience gathered on the grass to listen as speaker after speaker pounded his fist on the podium and declared that America is in the midst of a race war. "We don't have white power. Puerto Rican power, and who knows what else."

He spoke contemptuously of the established political parties. "The Ee-publicans and the Democrats don't represent you - they've sold out to the Jews," he said. There he made reference to the moderate leaders - people like George Wallace," and there were hoots of laughter.

The party's name was changed from the American Nazi Party in 1967, explained a member who declined to be identified, to identify it more closely with the German National Socialists whose beliefs it embraces. "National Socialist is just the proper term," he said.

About six men and women among the listeners applauded vigorously each time a speaker called for white revolution, an end to integration, and the immediate expulsion of all blacks, Jews and "mongrels" a term used variously to refer to American Indians and to children of mixed parentage.

The rest engaged in an informal beckling competition, apparently vying for the prime insults. Several police officers stood guard nearby, their faces impassive, but there were no flareups. One of the noisest moments of the rally, in fact, followed a speaker's explanation of the wearing of the swastika.

It's a symbol of our race," he said. It's a symbol of white revolution . . . Any white American who isn't man enough to put on a swastika - we don't want." And the young people in cutoffs who had been listening fell over each other laughing.