So, your arguments:
1. Admirals are natural desasters, similar destruction like nukes:
- So, just go for WCI, where the main island of Linlin is only her and her family, no casualities, or simply attack them on sea. Linlin was straight up at the sea for quiet some time for her way to Kaido. Or go for Onigashima, a single island only filled with pirates, no casualities again. Or catch him on the sea again. But they dont. And its not like KIzaru cared for casualities in SA.
2. "We dont know Greenbulls power yet, it could be radiation fruit"
- So they have an admiral which is simply unusable in any case, cause he would always cause radiation. Doesnt seem like very smart of the marines/ world government.
3. Other Yonkos would go for their head
- No. If one of 3 Admirals is able to take out 2 Yonko solo, there would be only 2 Yonko left. So it would be 2 rest admirals + akainu to take down 2 Yonko. Or do you want to tell me these 3 people arent able to do what Kizaru is able to?
4. Contracts like NWC
- You seriously want to tell me Marine Admirals and High ranked pirates have some "no aggression" contracts, which totaly contradicts the idea of bounties and wanted posters, or the simply whole existence of marines. You have an idea whats the job of the marines?
Instead of some half ass insults like calling me simple minded, try to use some real arguments, since your insults just show your insecurities and that you are unable to have a real discussions aka. lack of arguments.
1. no casualties? "it's only her family" lmfao bro...
You expect the marines to commit mass murder and kill everybody who is part of her family or allied to her just because she is a pirate with a pirate crew...
You basically expect the marines to commit war crimes and wipe the whole island off the map but also you still say there would be "no casualties"....
i dont even know what to say to that man
Kizaru definitely cared for casualties in SA he stopped doing big attacks after he realized the destruction he caused with the tree, Oda literally did that to show you how destructive he is and at the same time have a reason why he has to hold back.
2. could be used for radical means and would fit Akainu's character to get himself an admiral who can radiate an entire island but like i said we dont know that yet...
3. Thats not how story writing works though...
The characters within the story dont know who can beat who... why do i even have to explain that?
The Admirals dont know that they can easily wipe out the yonko, some Admirals might believe they can but some yonko also might believe they can defeat Admirals...
For example: Aokiji believed he could defeat Akainu, Shiki believed he can beat Sengoku and Garp etc...
Some characters might think they are stronger than others, doesnt mean thats the case.
The manga viewers have the best general idea about who is stronger than who cause we have that comparison based on battles and fights we have seen.
If the marines would attack the yonko in the story then they would do it with all of their forces in order to guarantee a crushing and overwhelming victory with the least casualties possible.
4. The yonko are part of the 3 great powers alongside the Navy HQ and the shichibukai.
The yonko are not normal pirate crews, they have a lot of territories and influence in the world, especially the new world.
The marines already have contracts with pirates like the shichibukai in order to counterbalance the influence and power that the yonko hold within the new world.
And we already saw that the WG made deals with Wano which was under a yonko's rule.
Also the yonko are not really bad for the world/marines as long as they reside on their islands they provide a lot of safety for it.
The marines already have to take care of another part of the world as well, having the yonko stop upcoming pirates in the new world is greatly beneficial for them as well.
Its only a problem when the yonko start to make moves or ally with each other.
