Nuclear Weapons were first used by Humanity in the 1940s, and in the following decades concepts such as Mutually Assured Destruction would give nuclear weapons the ominous connection to ending all human life. No nation wanted to be the first to utilize nuclear weapons as it would be both political and also regular-type suicide to do so.

In the 2300s the underlying reasons for the nuclear taboo have changed. With humanity spread throughout the stars, a single nuclear exchange on earth is no longer the end of human life. Radiation treatment and removal technologies have reduced the long term impact of nuclear fallout. Life and combat in space also remove much of a nuclear weapon's devastation, making it only marginally more powerful than conventional kinetic weapons and not an 'ultimate weapon' like it is within the atmosphere.

While the underlying reasons for the nuclear taboo may have lessened, the taboo itself remains and is still reinforced by modern media. Politicians who command nuclear arsenals are generally still unwilling to use them, even if their associated military forces are far more willing to do so.

Though military forces may not fear their usage, civilian populations certainly do.

Nuclear weapons typically aren't the first focus for military budgets, and even though nearly all conventional 'nuclear' weapons were replaced with various types of fusion based devices through the 2200s not much has changed in the overall weapon design other than devices becoming smaller, more powerful, and safer.

In the 2300s, the Magnetic Assembly started extensive research on the weapon systems, looking to develop technologies related to directed energy and high radiation neutron weapons largely with the assumption that they might need to be used against alien races or other unforeseen stellar threats.

The Grawla, while also using what are ultimately more primitive designs, have extremely mature and reliable nuclear weapon designs. Even with the difficulty of maintaining their technological advances against otherworldly threats, they have managed to maintain a strong production capability for robust, stable, small yield nuclear devices. The Grawla don't have the same nuclear Taboo as Humanity, and are very comfortable escalating to a nuclear exchange when threatened by non-grawla.