Probably nothing. Having a cousin who "worked for the State Dept", you follow the laws of the country you are in. It also depends whether you are "legal" or not.
Being illegal and getting pinched with a gun, pretty guarantees your going to spend a long time in the gulag.
Being legal and getting pinched with a gun, means you'll spend a long time in the gulag, until the US .gov decides whether or not you are worth a spy swap.
Sorry to let reality intrude....