The involvement of the United States in the war in Vietnam had a very negative impact on the social programs that were proposed by President Lyndon B. Johnson. The war harmed Johnson’s domestic agenda in at least three ways.
First, it took money away from those programs. The war in Vietnam cost a tremendous amount of money. So did the social programs of the “Great Society.” Government funds, of course, are not completely unlimited. Therefore, there was a tradeoff. The money spent on the war had to end up reducing the amount of money that could be spent on Johnson’s programs.
Second, it took Johnson out of office. President Johnson was eligible to run for reelection in 1968. He might well have won. However, the Tet Offensive and the war in general forced him into the decision not to run again. With him out of the running, Richard Nixon won the election and a move in a more conservative direction began. This harmed the domestic programs as well.
Finally, the war led to deep divisions in American society and these divisions did not help the Great Society programs. America started to divide into liberal and conservative camps much more than it had in past decades. The deepening conservatism, driven in part by anger at the counterculture and at civil rights and upheaval in the black community, led to much less support for Great Society programs.
In these three ways, the war in Vietnam made Johnson’s social programs much less viable.