How do biological weapons differ from chemical weapons and nuclear weapons?

Biological, chemical, and nuclear weapons are collectively categorized as weapons of mass destruction (WMD) due to their potential for indiscriminate, large-scale harm, but they differ fundamentally in their composition and effects.12

• Biological Weapons: These utilize infectious agents (such as bacteria, viruses, or fungi) or natural toxins to cause disease or death in humans, animals, or plants. Unlike nuclear weapons, they are incapable of destroying physical infrastructure or buildings. Their impact is often characterized by the potential for widespread pandemics and the difficulty of controlling their spread.23
• Chemical Weapons: These consist of liquids, gases, or solids designed to poison, blister, or disrupt the nervous systems of victims. They are categorized by their lethality and persistency in the environment, with some agents used to deny access to specific areas for extended periods.14
• Nuclear Weapons: These rely on nuclear fission or fusion to release massive amounts of explosive energy. They are uniquely capable of causing total destruction of city centers through blast, heat, and radiation, posing an extinction-level threat.516

The use of these weapons is a profound violation of ethical principles regarding the sanctity of human life and the protection of non-combatants. International treaties, such as the Biological Weapons Convention and the Chemical Weapons Convention, reflect a global moral consensus to prohibit these indiscriminate means of warfare.12