I am answering with the assumptions that
A) Bangladesh's population is as much your demo as USA
B) You eventually want to have presence in both countries

So here's some numbers- B'desh has only 7% internet penetration, but 80% of those use it at least once a day and the country is overwhelmingly a young country (under 55). If your service is youth-driven, that's a plus for sure.

As a result, web advertising through Google adwords is 79% less in Bangladesh compared to the US (http://tinyurl.com/nfqzxjc)
so that is one outstanding plus - save money, get eyeballs.

This high percentage of under-45 year olds makes social media and share-ability a big piece of your marketing (more free advertising), as well as the celebratory factor of a local person (your co-founder) having 'made it big'.

Without knowing much more about the product/service I'd say social virality and lower cost-per-click by 80% are two major points in favor of a Bangladeshi launch.

The decision is yours :), happy to have a chat with you on a call this week! We can talk about the urgency you are facing, and how you could translate the momentum from Bangladesh to the US market (short answer: depends, but can be done).

Best,
Arjun