How is it a USA Federal Judge can order Iran to pay 2.65 Billion Dollars to the families of the 1983?

Beirut bombing victims? He has no jurisdiction over Iran. They thumbed their noses at him and didn't even show up for court. He will never be able to enforce it. These people will never see a dime. So other than making a few people feel good, was this not a collosal waste of taxpayer's money? Isn't this just another one of those ridiculous law suits that is clogging our court system? Is this good governmental managment?