Imagine a bunch of frenzied Mimigas loose upon the humans... Now do you realize?
[something *like* Jenka said]
Mimigas don't blow up, but keep on going until dead, and their devistation is pretty limited to their immediate vicinity. Plus, they were previously intelligent, before being controlled. Personally, I don't see how Mimigas by themselves could wage war; unless there are a LOT of them. If each one is equivalent to a tank, then they would still very slowly make their way to each destination.
Just because the countries want to get rid of them or control them; doesn't really equate to some kind of stockpile of nukes. It's more like a virus affecting a bunch of dogs turning them into some kind of super rabies dog that follows certain sounds or scents.
They can be stopped, but like any horde of attackers; can overrun weaker adversaries. Especially when they don't go down to bullets, etc.
As for how do Frenzied Mimigas wage war at all... They are powerful, but far from some kind of nuclear weapon.
If Misery/Demon Crown user can warp them into any facility or target... then maybe we're talking. Send one there, another there. Suddenly you have Mimigas spread all over, and are unable to respond to them all. On the other hand, if there were Mimigas on the surface. Then there would be an endless supply of soldiers as long as there were flowers. That or if Mimigas multiply like bunnies D:
Mimigas are more like a wild fire (being spread by a pyromaniac?)
Maybe if you're talking about some kind of mechanical drone invasion going heywire from a virus, it might be close? Everyone wants that technology, and if you suddenly gained access to a fleet of them...
I might think... more along the lines of human tanks... or some kind of future soldier. Genetically altered, to be more suited to combat; equipped with some kind of biosuit to enhance strength, speed, and maybe pumped full of some kind of over the top rabies (non-ending) adrenaline drug. Then add in some kind of way to set objectives, maybe computer controlled vision. [See only targets that are assigned, so you don't kill everything in sight.] Maybe even tech assisted weapons targeting.
Add in medical nano-machines to assist in "regeneration"; and maybe an auto defiberlation system.
Drop in a bunch of super soldiers and wipe out the objective. The only thing not accounted for... is ammo and size. Non-reality I would say like mechs gone wild.
You could say the island is like a mobile base or aircraft carrier. That can drop in tanks wherever it pleases.
Still makes you wonder, how did the island not get targeted? If it did, what kind of defenses does it have? Or, what weapons does the Island itself have at its disposal?
Sorry if that was convulted xD I started at the bottom and went backwards...