You might not have any money in your pocket, but it doesn’t necessarily mean you are bankrupt. It takes a legal proceeding for the courts to declare a person bankrupt — or officially unable to pay his debts.
Despite the word bank in bankrupt, the word can be used to describe an entity that is short of something other than money. A bankrupt nation might not have the natural resources for its people to produce goods. A nearby country that could easily help but chooses not to may be considered morally bankrupt because of its lack of compassion. Or, maybe there is more to the story. That nation might fear that helping another will bankrupt its own shaky economy. (That is how bankrupt can be used as a verb.)