The military has always had a policy of discharging those who refuse a vaccine. It’s not new and not specific to covid.
They do have the option of granting exceptions if they think that you are too valuable to release or that you have a valid reason to refuse.
“The military has always had a policy of discharging those who refuse a vaccine.”
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I understand the military’s policy as the rapid spread of infections in close quarters can be problematic with respect to readiness issues. That said, COVID was not a great threat to young, healthy people and the long term effects of the vaccine were unknown (not to mention its efficacy). Not unreasonable for them to have concerns about taking the vaccine due to perceived concerns over long term risks.
The military rarely concedes to individual wishes, although the LGBTQetc personnel do seem to get plenty of accommodations and they may have been able to collectively resist the vaccine if they had wanted to fight it.