Let me explain this in a brief manner.
In August 1941, my grandfather and his entire class at the Leningrad Aviation Institute were drafted to form a battalion of troops commanded by a local bureaucrat, and thrown into battle virtually unarmed. Almost the entire battalion perished, but the overall war plan succeeded and the Nazis were stopped from entering Leningrad. This was morally permissible, because the very existence of the nation was at stake. The Nazis were planning to enter the city and butcher its populace or enslave them.
When a nation suffers from an existential, catastrophic threat, the gloves come completely off. In a national emergency, any means are permissible if they secure your population from dying.
We need to establish whether such a threat exists because that colors our evaluation of what needs to be done.