sentences:  In the 1970s and 1980s, Birnbaum shifted his attention to new policy initiatives.In the early 1970s, SSSJ concentrated on the utilization of economic pressures on the Kremlin.He had in fact testified in Congress on this concept as early as May 1965, was in close contact with Senator Henry "Scoop" Jackson's office regarding the Jackson-Vanik Amendment signed into law almost ten years later in January 1975.