The federal government cannot go bankrupt. In theory the government can default on debts, but in reality there is never a situation where the government would be forced to do so (it is always due to political dysfunction) -- as others have stated the US government is able to issue more money whenever it needs to do so, and thus can always satisfy any monetary obligations (though there may be negative consequences to doing so). Even if the government does default on its debts, it would not truly be bankrupt, because bankruptcy means that some higher authority has stepped in to decide what will be repaid and how, but the federal government is the highest authority. Likewise for the states, which cannot issue money but which cannot actually go bankrupt (as they have the authority to decide what obligations to meet or to fail to meet), something which has become relevant due to the enormous cost of dealing with COVID.