It depends on the jurisdictions in question. The degree of enforcability differs across pairs and depends on the specifics of the case and the nature of the ju

It depends on the jurisdictions in question. The degree of enforcability differs across pairs and depends on the specifics of the case and the nature of the judgements. But even where enforcability is low, which we believe it would be in this case, having a foreign judgement against you is a bad thing, particularly one from a major jurisdiction. As I explained in other comments-- even if you believe/hope it would be unenforceable it can still be unwise to ignore foreign litigation because you won't get a change to fight the case on its merits later should it turn out to be a problem. Perhaps if you were facing a likely unenforceable foreign case that you were sure to lose then you might be best off ignoring it.