I personally feel that Alexander the. Great did nothing to deserve that title of greatness. Eventually his pride caused him to fail from an article written by a historian is it biased credible

It’s biased because its an opinion. You know this by the use of “I personally feel,” it’s arguable. Credibility depends on who wrote it and their field. For example of an article about physics written by a professional chef obviously isn’t credible because they have no experience in the field. However if the chef wrote on food then the article would be credible.

  the domino theory states that  if one country in a region came under the influence of communism, then the surrounding countries would follow in a  domino  effect.