Killing them certainly wouldn't be easy.
But at least we could be sure that we can make it stick, if we ever got to that point.
And Uriel's warning is specifically about keeping the Coins imprisoned in our Hell, not about attempts to destroy them, or their inhabitants.
1) In order to kill five or six Primordials and their subsouls in 2E, while scaring the other ten plus Primordials into surrender?
The Primordial War-era Deliberative required almost a thousand Celestial Exalts, a million plus Dragonbloods, and tens of millions of mortals, Dragon Kings, Jadeborn and spirits, and the support of two Primordials.
Plus all the infrastructure that was built up for that war.
The casualties were immense; even the Celestial Exalts had many of their number die multiple times over.
And even then, we got Neverborn and Hekatonkhires from the dead, because entities of that weight dont die easy.
Molly is one Infernal. And not even an elder Infernal.
That is not Infernal Exalt business.
It may be baby Primordial territory, maybe, but its not Infernal Exalt territory. When we get to a point where we can comprehend the ramifications of something like that, then we talk.
Not to mention that the Catholic girl who went to Sunday School would consider that there might be a reason they were cast down after rebelling instead of being unmade.
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2)Uriel's warning is about giving Lucifer a justification for more freedom of action.
He used the phrasing "beyond mortal temptation" deliberately.
I'm not sure killing angels would do something as bad as neverborn or anything like it. Mind you they may serve literal purposes for the universe which would suddenly be imbalanced but I figure on a certain level their just completely different types of beings even if in power their similar to plenty of things.
I forget many of y'all didnt go to Sunday School.
In Christian mythology, when Lucifer rebelled against God, Michael cast him down along with a third of the angels of heaven.
Mankind being cast out of the Garden of Eden can be traced back to Lucifer tempting Eve.
The Flood can be attributed to angels coming down to Earth and fucking around with human women, creating a class of giants who dominated the Earth and forcing the White God to do a server reset.
Angels fucking around metaphorically and literally can be a very bad thing for anyone in the vicinity.
You have to figure that when Lucy and his supporters were cast out of Heaven, they werent destroyed for one of three reasons
1)The White God couldnt do it
2)The White God didnt want to do it
3) They fulfilled a purpose even after Falling
And in the Dresden Files, angels are system killers.
To quote Butcher:
Are Mab and Titania equal to the Archangels in terms of raw power? What about the Mothers?
Nowhere close. Like, /nowhere/ close.
Angels are so far beyond a being like Mab that there's just no comparison to be made. Mab might be able to, if she really worked at it, enchant the world into an ice age. But an angel could destroy the SUN.
I mean, for you and me, there's no difference between them. But relative to one another, there's a HUGE difference. The angels have far more power.
But.
Mab has far more /freedom/ in what she can do with her power. Bigger and stronger doesn't mean you win the fight all by itself. Ask a hawk the next time you see it being run out of town by songbirds. Mab might have less muscle, but she can actually apply her muscle to a huge variety of situations--angels exist behind limits hardwired into their very beings.
Angels are, in this instance, kind of like a super powerful AI. Within the world of the computer, it's not a force that can be effectively resisted. It runs the place.
But that same AI can only do what it's been told to do--and Mab is a user with mid-level admin access. She can't command or delete those AIs, but she knows why they were made, how they work--and how to get around them if necessary.
Mab isn't stronger than an angel. But she is, in most situations, far more powerful.
But MY answer was going to be to say that angelic powers simply exist on an order of magnitude beyond that of anything happening on a level a mortal could understand. I mean, who actually has more power in a production: the lead character, or the lowly stage hand who is running his lights and audio. That person playing the character might get the limelight, but the dude in all black is running the show.
A lowly footsoldier angel is a power of an order of magnitude greater than all the local-scale supernatural beings we've seen in the Dresden Files put together. I mean, it wouldn't be a fight. The angel wins, hands down.
Except the angel wouldn't ever win, because more than likely the angel would never be allowed to fight. It's a being of such power that it exists behind strict walls of control, limits beyond which it simply cannot, by its very nature, tread. When an angel IS allowed to smite something, you get rains of fire, flaming cities and pillars of salt. But mostly they are epic beings for epic times and epic actions. It isn't their place to interfere in the lives of the beings of the universe--angels exist to preserve the nature and order of that universe just so all those little beings can do what they do.
Uriel is being a cheeky bugger and taking terrible chances, doing what he is with the Swords, trying to get involved in mortal affairs without actually getting involved. Only Lucifer has danced that close to the line before, and that one didn't work out so well.
The least angels are supposed to be off the scale. Just that they are bound by rules of what they can and cannot do.
I dont think we want to test even a Fallen Angel's latitude of action.