DURING MORE THAN 50 years of civil-rights advances for which he could claim a lion's share of credit, A. Philip Randolph was a dominant figure. Mr. Randolph, who died Wednesday at the age of 90, fought for and won the respect of black and white Americans with a blend of militance and dignity, topped with a marvelous flair for the dramatic. His tactic, while always nonviolent, included effective doses of threat and bluff-necessary weapons in what he referred to as the "revolution the Civil War left unfinished."

From his days as a daring editor of a radical magazine to his inspiration of 1963-the march on Washington-Mr. Randolph sought for American blacks not hostile withdrawal, but complete participation in this country's educational and economic opportunities. He insisted that civil rights and full employment were inseparable-that black and white workers would have to fight together for economic rights. To achieve this strength, Mr. Randolph organized the Brotherhood of Sleeping Car Porters in 1925 and went on to do battle with leaders of the old AFL and later the AFL-CIO over racially discriminatory policies in the house of labor.

His talent for constructively irritating and shaking authority extended well beyond the labor movement-right into the White House. In 1941, Mr. Randolph warned President Roosevelt that tens of thousands of black people would march on the segregated capital if discrimination in wartime industries did not end. The upshot was establishment of the Fair Employment Practices Commission. Seven years later, he warned President Truman that unless the armed services ended their Jim Crow rules, blacks would refuse to serve. That worked, too. Then the 1963 march was to be a strong factor in the passage of the Civil Rights Act of 1964, prohibiting discrimination in accommodation, employment and unions.

Philip Randolph was a steady man and a man of great vision.