This is explored at length in the books. The wizard supremacists are an allegory for race supremacists, and it’s pointed out repeatedly that they’re delusional, broadly impotent, and small-minded. The death eaters believe so completely in their godhead and his divine right to rule that they neglect to consider even the most basic countermeasures or alternatives. There’s some “death of Stalin” paranoia but it’s overwhelmingly unforced incompetence.

Voldemort, likewise, blocks out even the potential for his lessers to outdo him. He is utterly infallible and his insecurities as an incest orphan to a fallen house will not allow him to feel any differently. Meanwhile, he’s been repeatedly circumvented and beaten by a group of teenagers, and his brewing plans will lead to the complete genocide of wizardkind upon reaching the world stage. It perfectly encapsulates the way race supremacists view the world and why they fail so frequently. The enemy is both strong and weak.

Darn shame rowling’s turned into what she hates. She wasn’t terrible at writing populism 101.

Wizards would be rounded up and experimented on to try and find out how to make it an injection to make super soldiers. There's absolutely no way wizards and magical beings wouldn't end up in test tubes.

I had trouble believing Harry Potter as a kid. The whole house elf thing seemed unrealistic. Then when I grew up, I realised English people really are that racist.

Harry Potter and the poorly-constructed magic ruleset.

Harry Potter and the Mysterious Ticking Sound

Imagine the IRA, except they can fly, go invisible, or simply step into a phone booth or fireplace and vanish, and had an entire other dimension they could disappear into where they could be self sufficient.

Technology means nothing if you don't even know who you enemy is.

The reason Hermione is sworn to secrecy about the wizarding world is that they know if muggles found out there was a deep state, the revolution would be swift.

That's one of many many plot holes in Harry Potter.

There's really no depth to the world building beyond, "What if British public schools taught magic?"

It doesn't make sense in any context beyond that because the author never considered it from any context beyond that. Whenever you run into some crazy crap in HP and wonder, "Why TF would anyone do it that way?" The answer is almost always, "Because that's how they do it in British public schools.

Honestly, I only really see wizards losing immediately in England, lol. It's canon that many wizards can use spells silently and/or without a wand, and some even create their own spells; they could likely incapacitate a soldier (or many soldiers, depending on the spell) without raising suspicion by having to aim a wand or gun.

I dunno, Magneto gives the US Army a run for their money in X-Men - I would think a similarly talented or experienced wizard would have comparable powers.

It comes down to how powerful static wards are, and how much technology just gets corrupted by magic. The real power of the wizards is memory and time manipulation. Close range is definitely in favor of wizards, you can't surprise them unless they are intentionally careless. They can always go back a few hours and ambush you back. Chaos would ensue if they deleted every memory before 5 of a handful of leaders.

The tech killing thing is poorly defined, but hogwarts seems to disable electronic devices within a radius. If it's similar to an emp, it may have countermeasures, but it's hard to say they also work on magic. Operating within the radius of somewhere like that would be difficult.

There's also the animagus issue. Every dog, cat, bird, or bug is a potential spy or assassin that is practically undetectable.

The big question is can spells stop a large bomb/nuke. Even if they couldn't, it would be possible for wizards to escape the blast zone pretty easily, unless they couldn't detect the attack.

I think the big weakness would be sniper fire that may be fast enough to prevent reactions at the borders of wards.

I cast ICBM

of course muggles would win a war against wizarding folk, that is why they made the international statue of secrecy (also cause jkr is a hack who never wants to bother extrapolating from the consequences of her own worldbuilding)

If wizards were incapable of shielding against fast moving projectiles, they would have more spells dedicated to creating fast moving projectiles against their opponents.

I'm not much of a harry potter fan but wasn't that the whole point of being in hiding

There’s a WP. Voldemort succeeds and then gets drunk on his own power and attempts to take over the muggle world (pure blood and all that) and he promptly gets his ass handed to him by the military.

Obligatory Harry Potter With Guns trailer

As nonsensical as it is, giving the limit of the suspension of believe necessary to keep the world reasonably coherent, the wizard world has a solid grasp on the non-magical world while it's a given (literally a given, it makes no sense otherwise) that the people from the normal world have no idea magic exists, other than what is leaked and relegated to fairy tales (it's our world).

Wizards, their institution and governments, their own citizen are aware of what weapons are. Harry himself of course knows what a gun is and could potentially grab a number of them to prepare for war.

So it's an implied obvious implicit answer that even a limited mastery of magic vastly overpowers weapons. Which is obvious if you consider that in the magical world they are aware of the "laws" of physics AND the extra laws of magic.

They just know more about how the world works, how to inflict death and how to protect against harm.

I cast "A belly full of lead".

I think the guns would help against wizards as much as they help against oppression. They are a helpful tool, for sure, but the ability to communicate and form plans is massively superior. And wizards, like modern tech giants, can impede that.

*most powerful spell kills upon striking

*is also clearly visible, dodgeable, and deflectable

Three words: Close Air Support.

1 GBU-39 would dust that steam engine wiping out whole generations of wizards. AIM-9 Sidewinders piloted by someone with confirmed kills for those weird skeleton death birds. Ezpz.

I've never read the books, but I'm curious what the point even is of going to Hogwarts to hone your magic in secrecy. What is the magic applied to long-term? What do you do with it after you've graduated?