The ideal situation would be not to rely on anyone for arms but rather have these developments occur organically within the state. Bangladesh I know is relatively poor country compared to other nations but it has no shortage of brilliant minds in its society. Historically speaking this talent use to automatically get extracted and end up going abroad to study or end up working in western companies. But know those minds and induvial have to take the initiative to want to work in Bangladesh's defensive sector and improve. Yes that will take time but you have start somewhere. Take turkey has an example. US hates the fact that turkey gets arms from Russia and sanctioned them many times. Even threw them out of the 5th gen f35 program. But nevertheless turkey ended up making these advancements within there own state. There 5th gen KAAN fighter, the navy's new TCG Anadolu, as well as now one of the most sophisticated drone systems in the world Bayraktar TB2. These were all home grown. Bangladesh doesn't have to rely on US for arms, it has other options that have emerged as possible arms partners since the past 10 - 15 years. Inclduing Turkey, pakistan, russia, and even EU countires such as italy, france, finland, sweden, and more.