Frame challenge: there appears to be a fundamental problem with operational security.

Substantially all of this nation believes that the oil is demon's blood, yes? But the plan to nuke all the oil has to be kept secret, or other countries wil intervene to prevent this environmental catastrophe for the whole world.

Why won't the population of this nation rise up against the plan to bring all the demon's blood to the surface, making it far easier for it to hurt them?

They can't be told that the plan is to nuke it, as anything you tell a whole nation is inevitably going to become public knowledge, triggering outside intervention.

Frame challenge: there appears to be a fundamental problem with operational security.

Substantially all of this nation believes that the oil is demon's blood, yes? But the plan to nuke all the oil has to be kept secret, or other countries will intervene to prevent this environmental catastrophe for the whole world.

Why won't the population of this nation rise up against the plan to bring all the demon's blood to the surface, making it far easier for it to hurt them?

They can't be told that the plan is to nuke it, as anything you tell a whole nation is inevitably going to become public knowledge, triggering outside intervention.