Why anaerobes die if exposed to oxygen?

Why anaerobes die if exposed to oxygen?
Life first evolved without oxygen, so anaerobes are controlled to certain types of microbes and archaebacteria that survive in anaerobic environments.
Oxygen is an extremely reactive compound. It can produce various oxygen radicals resembling hydrogen peroxide and superoxide that will react near and break down proteins and nucleic acids that are essential to life.
Aerobic and aerotolerant anaerobes enjoy a number of enzymes such as catalase and superoxide dismutase to hastily eliminate these oxygen radical before serious trash is done. Most anaerobes do not and cannot repair the damage.
Strangely plenty, the reason aerobic respiration works so effectively is to a degree because of how reactive oxygen is. Aerobes not only widely read to tolerate something deadly, but to use its reactivity to their control.
Anaerobes are biological organisms that used Carbon Dioxide for respiration. Aerobes use Oxygen. If aerobes (like humans) are deprived of oxygen, they will die.
That's an interesting question. I other thought they were anaerobes because they didn't USE oxygen, not because they be not EXPOSED to oxygen. Hmmm.