The case is not expelling Muslims. The case is creating anarchy. When creating anarchy is the reason and China is the main opponent here who can gain access to deep sea directly via Miyanmer, and it is a serious thing. USA can not establish it's hegemony in the region if China has such frequent access through Bay of Bengal! So everything is possible if you want to prevent China. Tell me what would happen if Bangladesh started war with Miyanmer? Probably we got the support from USA, and the result could be a war zone for international players! So fare could be the same as Pak - Afghan region.
However, it's not my idea. Let
@Old School answer this in details, it's his idea but I found his logic appealing for some reason I already explained.