Well, that's what the NAZIS thought was a good citizen.
Then there is the school of thought that a good citizen pays taxes without complaint, serves on a jury when called, goes to war when called, and so on.
We still haven't got out of the NAZIS norm here.
A Suggested Definition: A good citizen is one who acts with consideration for fellow citizens.
The term citizen comes from from Anglo-Fr. citezein, sense of "inhabitant of a country".
A good citizen is a good neighbor.
When people get together in groups, they can become pretty dangerous.
When they get together to form a government, they can get seriously dangerous.
We humans have this tendency to slip into what's known as 'group think' where we can give ourselves permission to behave in ways that we would not think of doing as individuals. This problem increases with the government, where most people, even religious organizations, actually apply a different moral standard than is applied to other groups and individuals.
The proper function of government is to keep citizens from harming each other.
The function of responsible citizenship is to keep the government from harming citizens.
How to do that?
Become an informed citizen.