What do people mean when they say we have enough nukes to destroy the world?

Question

Are they just talking about erasing cities/mankind from the surface or the combined energy from them all is enough to significantly disfigure the surface? Or would it be the aftereffects of the bombs that cause the destruction?

In: 1

Answer 1

The after effects of exploding the collective nuclear assets of the world (~19,000) would cause far reaching long term impacts on a global scale. Life would likely not survive. The amount of debris in the air would block sun, plus the radiation impacts would kill for many years, birth defects would go exponential, etc.