Honestly I don't see why any country would ever enter a long-term agreement with the US. The Constitution says that the president negotiates international agreements but that Congress must ratify them. Due to procedural rules basically making it impossible for Congress to pass legislature, any agreements that don't go through Congress are simply executive agreements that can be terminated with a stroke of a pen by a future president. This means that any remotely controversial agreements can't be expected to last beyond the current president's term.