Melissa Conley Tyler is National Executive Director, Australian Institute of International Affairs.

With the election of the Abbott Government, expect to hear a lot about the national interest. The last time the Liberal-National Coalition was in power it produced a foreign policy white paper called In the National Interest. Arguably the concept is a touchstone for the Coalition in the same way that 'middle power' and 'good international citizen' have been for Labor.

But the national interest can be difficult to pinpoint and is inherently contestable. Almost any foreign policy can be defined as being 'in the national interest'; it all depends on your point of view.

In a recent article in International Affairs, ANU Professor Ramesh Thakur argues that a better concept is a 'balance of interests' framework which recognises that, at times, there will be competing interests and that policy makers will need to take a balanced approach. The process of determining which interest to prioritise and how to manage conflicts of national interest will be influenced by a range of domestic, regional and international factors.

To illustrate, look at Australia’s six key relationships: India, Japan, Indonesia, China, US and South Korea (as set out in Foreign Affairs chief Peter Varghese's 6-2-N formula).

In each case there are potentially conflicting national interests in security, economic prosperity and a rules-based international system.

Is it in the national interests for Australia to sell uranium to India? Not doing so damages Australia’s trade and security interests with India. Yet Australia has a core interest in the maintenance of the non-proliferation system. A determination of the national interest will need to balance Australia’s economic interests with its interest in maintaining a rules-based international system and benign security environment.

Is it in the national interest for Australia to take Japan to the International Court of Justice over whaling? Australia opposes Japanese whaling in order to uphold international law and conservation norms and appease a domestic constituency. However, the ICJ case has potential ramifications for security and economic relations, including progress on a free trade agreement that has stalled somewhat since 2012. Former Foreign Minister Alexander Downer has characterised the ICJ case as an example of where Australia has 'cut off our nose to spite our face.'

Is it in the national interest for Australia to turn back the boats to Indonesia? It may meet domestic political interest but imperil important security and economic ties and undermine a rules-based international system.

Is it in the national interest to exclude a partially state-owned Chinese company, Huawei, from helping to build the National Broadband Network? Security interests and economic interests may conflict.

Is it in the national interest to station drones on the Australian territory of Cocos Island? The national interests in the security alliance with the US may need to be balanced with the requirement to acknowledge regional sensitivities.

Finally, how would Australia balance its economic and security interests if drawn into a conflict on the Korean Peninsula?

The pursuit of the national interest is likely to define the foreign policies of the incoming government. The problem is that there is no end of things that can be argued to be in the national interest. The difficulty the new government will face is prioritising which specific national interest to pursue at which time, a task made more difficult by the fact that these interests often conflict with each other.

Australia has proven countless times that it is able to take a balanced approach to choosing which of its security, economic and global interests to prioritise, and how and when to make trade-offs. But the concept of 'national interest' can mask the process (or, as Ramesh Thakur terms it, the 'human agency') involved.

Let’s add an 's' to the national interest.

Photo by Flickr user Ian Wilson.