The literature on the drivers behind bilateral treaties implies an assumption that international treaties are entered into primarily to achieve national objectives, not partisan political goals. This paper investigates whether this assumption is valid, using as a case study the recently enacted US–Australia Free Trade Agreement. A stated original purpose for the agreement—increasing access to the US market for Australian agricultural products—would yield significant economic benefits for Australia. However, when it became clear that this goal would not be achieved, the objective of the Australian government shifted. The most plausible explanation for the shift is that domestic political objectives had moved to the fore and prompted the government to pursue and adopt the treaty despite some evidence that it might not be in the national interest to do so.