This is one of my greatest fears and I think it may be the ultimate demise of humanity.
Imagine a virus that has a 90% mortality rate among East Asians, but only a 10% mortality rate amount Europeans. Or vice versa. It breaks the concept of mutually assured destruction because the attacker might believe that other nations do not have the ability to strike back, or they can construct feasible defenses against a counterstrike. Release the virus then close your borders and ports.
It also would of course be easier for a non-state actor to construct a world-destroying biological weapon compared to an arsenal of nuclear weapons. You can hide a biological weapons lab anywhere.
Imagine a virus that has a 90% mortality rate among East Asians, but only a 10% mortality rate amount Europeans. Or vice versa. It breaks the concept of mutually assured destruction because the attacker might believe that other nations do not have the ability to strike back, or they can construct feasible defenses against a counterstrike. Release the virus then close your borders and ports.
It also would of course be easier for a non-state actor to construct a world-destroying biological weapon compared to an arsenal of nuclear weapons. You can hide a biological weapons lab anywhere.