Are there explicit laws against bitcoin? It seems unlikely that the OCC is going to just seize a bank when its following all applicable laws and compliance mech

Are there explicit laws against bitcoin? It seems unlikely that the OCC is going to just seize a bank when its following all applicable laws and compliance mechanisms. Some banks (depending on the location and size) keep foreign currency on their books so you would just need to account for it by the same manner unless there is some definition as to what constitutes a foreign currency for accounting purposes.