For twenty years, in preparation for a possible interdimensional war, major human countries have focused not only on domestic defense but primarily on deterring deities from other worlds.
Among these, nuclear bombs are currently the most powerful and only deterrent weapon humanity possesses.
Before nuclear bombs existed, no other weapon could compare to them, including atomic bombs and hydrogen bombs.
Theoretically, the most powerful hydrogen bomb has no limit on its yield; with enough materials, one could even create a bomb capable of destroying the entire Solar System!
1.5 billion tons of yield is certainly not the maximum yield for a hydrogen bomb humanity can produce at present.
However, to avoid attracting more attention to Earth, in accordance with a treaty signed by various nuclear powers, all nuclear tests in other worlds must be reported to the United Nations, with yields below one million tons and only detonated underground.
