Of course the fabled military- industrial complex exercises formidable clout. There's an election coming. Of course every fly-blown congressman is keen to instal fresh weapons of death in his own backyard. There's always an election coming. Something deeper than that has burned into the American psyche through the long, cold years.
Threat equals sacrifice - equals a way of life.
All the easy stuff about world leadership and solitary superpowerdom doesn't resonate unless there are dark forces to challenge such hegemony. Therefore, there has to be threat. If scary Soviets can't play the villains any longer, then new villains have to be confected. The move to construct an NMD shield is thus more instinctive and profound than mere politics would have you believe. It is the reward of technology for so much sacrifice.