How do "Magic/Power Politics" work?

[~xFellWardenx~]

I see lots of references to how differently politics work in a game with magic and stuff in D&D, especially if the levels are higher (though even with overall low-level NPCs and low-level spells it's apparently still a big deal) but it's always been very vague as to how this is the case. I mean, it makes sense on a very general level, but I'm not a very smart person so I don't really know what stronger-than-possible-IRL people and magic do to make politics different and what becomes different about them. Can someone help me out?

[deuxhero]

Unless countered by magic, spying is easy, communication is easy and assassination is easy.

[jedipotter]

The problem is that magic can do a lot of things. Though a lot of it is basicaly like modern technology. So anything that happens in the modern world can happen with magic too. You can use magic to listen to a conversation just like you can with technology. And magic can do a lot more too. Illusions, shape changing, mind control, mind manupliation, teleporting and scrying and more.

You get three choices for a world:

Mundanes are Useless In this world, the mundanes, are clueless and helpless. A single spellcaster with a single spell could rule the world, if they wanted too. If the spellcasters and magic users don't care, then it is a normal world. If they do care, they can control or rule the world. Lots of fantasy is here. Lord of the Rings, for example.

Savy Mundanes In this world, mundanes know about magic and take steps to block and stop it. Pass words can prevent simple shape changers, as can questions, for example. As soon as someone does ''anything strange'' you can grab them and check for mind control, or do things like ''this order can only be changed by three captains at the same time''.

Magic vs Magic In this world everyone has magic. So it is all the magic vs all the magic. Effects block scrying, divinations reveal things and so on.