In God's kingdom, certain creatures are necessarily given the powers needed to perform their duties. Satan believed that his God-given powers qualified him to function as an independent god. As evidenced by the prevalence of misery, disease, accidents, and war in his dominion, we now know that Satan is incompetent.
The Quran clearly states that Satan was an angel, by virtue of the immense powers and rank bestowed upon him. This is why he is addressed as an angel (2:34, 7:11, 15:29, 17:61, 18:50, 20:116, 38:71) prior to his fall. By definition, a jinn is a fallen angel (18:50). Satan's rebellion teaches us that the angels were created with minds of their own, and absolute freedom of choice (2:34).