Talking to each other and collaboration is the way of a civilized humanity. A pre-emptive creation of a military branch is not.
Yes, there are many downsides to war, those millions of dead people you mention amongst them. The thing is, just because you have decided the downsides of war - millions of dead etc - do not weigh up to the potential upsides does not mean your neighbour thinks the same. Eventually you'll get a neighbour who sees you as ripe for the picking, unprepared for war as you are. Some people might die, sure, you being one of them, but in this neighbour's eye the trade-off is worth it.
Humans are a belligerent species. Just wishing for this not to be the case does not make it so.
[1] https://en.wikipedia.org/wiki/Si_vis_pacem%2C_para_bellum
On the other hand kinetic bombardment is much better than than nuclear exchanges for the people left alive and makes nuclear weapons pretty close to obsolete.
It’s like nuclear weapons.
You cannot reverse or stop technology from progressing and you can’t stop governments from using that technology to build weapons.
How many wars did it take for humans to adopt a different “steady state”? And even now it’s not a real steady state.
Maybe we have more lessons (I.e mistakes) to learn from in space where billions die. Hopefully not. Hopefully we let the 20th century continue to instruct us.
Meanwhile world leaders spend well over $1 trillion a year on their militaries. What else could we do with that much money?
There’s absolutely no reason to launch humans to space for the purpose of operating space-based machinery.
The current us space force has the sole purpose of supporting ground wars. And when they start battling in space in a hundred year, they will nuke planets or throw rocks on them.
Why do you think the US has space superiority? Currently the US has no capability to send humans into space, we use the Russian Soyuz program for this.
Even if you don’t believe current President is incompetent, don’t rule out a future one you might hate. If such a force existed, you can be sure it will be used for evil and for extracting favors for private entities eventually. These things are never done for the good of the regular people. SpaceX doesn’t have a lawful society to operate in already?
While there are some downsides, I actually think this is a net positive. War-time, or at least the preparations for potential war-time (as all military endeavours actually are), usually lead to the greatest scientific and technical advancements. Just looks at WW1, WW2, the Cold War. I think we are now entering a "space cold war". Hopefully it can stay a "cold" war. But it is exciting to see what developments may come along.
The other upside, is that if the US achieves space superiority (which it already has, but if it develops the means to properly enforce it - which it is trying to do with this space force), it will open up the potential for proper commericialization. The US will be able to enforce space trade law, customs law, private property in space will be made possible. This will enable companies like SpaceX to have a proper legal framework within which to operate.