If you don’t want to build anything that could ever potentially be used in the manufacture of those weapons, you probably shouldn’t be building open source software or contributing anything to do with any programming language at all.
They want the CoC to be able to silence undesired speech in the first place, and if they refuse, it becomes their strawman to allow them to keep arguing the same thing all over again.
To me this reeks of the "paradox of intolerance" e.g. "you cannot be inclusive without allowing people to say things you don't like".
You may or may not agree with this stance and that is totally fine. You’re still free to use the software for whatever you want; you can also go ahead and fork it, or create a new community endorsing this use. If enough people agree then it will thrive. That’s the beauty of it!
A specific community has the freedom—within the bounds of legality—to decide who is welcome to participate.
Be that as it may, we wouldn't have computers or the internet if everyone acted like that.
I do not identify as a leftist, and would not be considered one, but as an aerospace engineer I would never work for something that aids the US war machine.
Those weapons are never used in "defense". Do they defend an unsustainable way of life ? Sure.
How is that not defence?
Better stop using computers and the internet then.