Given that ICBMs regularly enter a suborbital spaceflight, it seems to me that space is already very much militarized as a potential zone of conflict.
Also, given that China is planning on developing a militarized series of weaponized satellites and a base on the moon, while Russia is also planning weaponized satellites, it is a logical decision to ensure that other nations at a minimum prepare for a potential conflict in space, regardless of the apparent "defensive posture" of China and Russia.
All in all, any development of infrastructure regardless of its potential to militarize space is a great thing for the future of earth. Logistical and resource needs will eventually necessitate mining of materials from asteroids, comets and even more likely: the moon. All of which will reduce the resource burden for metals on earth (assuming a commercial extraction process which would drop material onto the surface). This could see an end to strip mining and potentially even the processing of ores on earth which create significant environmental harm. It will also take us one step closer to developing a colony on mars and reinforce that colonys sustainable outcomes over time.
All in all, I see this as a good thing for the world, not just the US.