Why Mohammad bin qasim attack sindh?

Muhammad bin Qasim attacked Sindh in 711 CE primarily to expand the Umayyad Caliphate's territory and spread Islam. The invasion was also prompted by a request for help from local rulers who were facing internal strife and external threats, particularly from the Hindu ruler Raja Dahir. Additionally, the region was strategically significant for trade routes, making it an attractive target for conquest. Bin Qasim's campaign resulted in the establishment of Muslim rule in the region, which had lasting cultural and religious impacts.