Reminds me of a light novel, where the MC used witches' magics to bootstrap his industrial process, instead of fighting directly with magic.
Out of curiosity, do you recall the title / author?
I'm not a good writer, so this will likely end up a military porn story to the tune of Salvation War[1] - so perhaps it's best if it remains unwritten. But really, if you think about it, the Wizarding World wouldn't stand a chance against even single organized operation by a modern muggle state military.
--
[0] - https://www.youtube.com/watch?v=BDX5uToKuPY
[1] - https://tvtropes.org/pmwiki/pmwiki.php/Literature/TheSalvati...
My favorite little bit of the series so far was how humans eventually figured out what makes Basilisks tick, managed to replicate it on an FPGA, and turned CCTV cameras into defense turrets.
[1]: https://www.reddit.com/r/guns/comments/gwl0v/why_harry_potte...