[quote:] "He was removed was because he had plans to appoint his next son Sheikh Abdulaziz as heir appareant, thus pushing Sheikh Hamad aside."

I'm aware of this but why did sheikh Khalifa suddenly decide to remove shk Hamad after all these years?

As for shk Mishal, it was obvious the Shk Hamad did try to prepare him to be Heir Apparent. I remember seeing him take him on several official visits. Shk Fahad is what could be described as a "radical" Muslim and I heard that he WAS offered the position of Heir Apparent but declined it.