Final answer:
Bakr was an effective leader due to his military victories, strategic decisions, and ability to unite and expand the Muslim community during a critical period of its early history.
Step-by-step explanation:
Details supporting the idea that Bakr was an effective leader include his military victories and strategic decisions, which were critical as the early Muslim community faced the challenge of succession after the Prophet Muhammad's death. As one of the elders of the community, he was well-respected and popularly chosen, displaying his popularity among the tribal leaders. His leadership was characterized by suppressing revolts among Arab tribes and initiating campaigns against Persia and Byzantium, increasing the loyalty of the Arab tribes and expanding the faith. Moreover, his ability to unite a splintered community and maintain the momentum of Islamic expansion exhibits his diplomatic skills and strategic acumen.