Loan in a foreign country

I am a permanet resident alien of the United States and have a student loan debt in a foreign country. The loan is 16 years old and no payments have ever been made due to my financial difficulties. I understand that the foreign government can pursue the debt in the US, and probably will since it is a significant amount. I'm wondering about the "mechanics" of how they can garnish my wages. Do they obtain a judgement in a US court, and does it have an effect on my US credit history? Any help would be great. I am looking for as much information as possible before I negotiate a payment plan. There is no statute of limitation on student loans in that country.