For better or worse, removing a Senator is hard to do. The Senate would need two thirds of Senators to agree with this removal. Even if every Democrat agreed (and I'm even including Sinema and Manchin here), you'd still need 17 Republicans to vote for it.
Of course, it's a good thing that it's hard to do this. Otherwise, the next time Republicans controlled the Senate, they'd start kicking out Democrats one after another for the most idiotic of reasons.
Honestly I think it's worse. I'd be fine with the occasional good senator being removed if it was equally easy to remove the bad. More turnover in general wouldn't be a bad thing for Congress, especially if it's in response to something specific. That indicates a somewhat healthy democracy where senators are held accountable to something
I just don't believe that all of them in their entirety are against the military, most people support the military and it is one of the unifying things about all the parties in the political landscape