You said: Bush and Co. want long term US Military dominance in space and we need nuke powered spaceships to do it.

Yes, the US wants to have military dominance of space, but probably not in the manner you think. Our air, land, and maritime forces are becoming ever more dependent on space systems. This includes things like intelligence, surveillance, reconnaissance, communications, navigation, missile warning, and weather monitoring. As we become even more dependent on space, the need to protect our systems from others becomes more important.

According to joint doctrine (JP 3-14 Joint Doctrine for Space Operations), space control has 3 aspects*:

1. Protection of US assets from attack and interference,

2. Preventing others from exploiting our assets for use against us, and

3. Negation of other nations' space abilities. There are the "5 Ds" that comprise negation:
a. Deception
b. Disruption
c. Denial
d. Degrade
e. Destruction

You don't need nuclear powered spaceships to do any of that. That isn't to say that nuclear powered spaceships couldn't be useful, but they certainly aren't necessary for space control.

*Air Force doctrine lists 2 types of space control: Defensive Counterspace (effectively combines protection and prevention), and Offensive Counterspace.