Harvard political scientist Graham Allison popularised the term “Thucydides Trap” to describe the danger that arises when a rising power challenges an established one.
The idea comes from the ancient Greek historian Thucydides, who argued that the rise of Athens and the fear it created in Sparta helped make war inevitable.
Allison originally used the concept to examine the rivalry between China and the United States, but it has a broader application. It is really a way of thinking about what happens when a dominant force begins to lose its grip and the challenger starts to look not only stronger, but more confident.
That makes the question worth asking in Australian politics: has the Liberal Party fallen into its own Thucydides Trap?
For most of the post-war era, the Liberals were the dominant force on the Australian centre-right. But over the past 20 years, that dominance has been steadily eroded. Labor has become more competitive and electorally successful, while the conservative space has fractured, with One Nation drawing support from voters who may once have been assumed to sit comfortably within the Liberal orbit.
The 2025 federal election underlined the scale of the problem. The Liberal/National Coalition was reduced to 43 seats, (now 42 post Barnaby’s runner)and the Liberal Party itself held just 18 seats in the House of Representatives. That is not just a bad election result; it is a sign of a party that has lost its old sense of inevitability.
At the same time, One Nation remains a real presence on the right. In the 2025 Senate vote, Pauline Hanson’s One Nation secured 5.67% of first preferences nationally, and last week won their first Reps seat (apart from the turncoat Joyce) by winning the by-election in Farrer with 39.5% of the vote after preferences. That is unlikely to make it a potential government at the next general election, but it does make it a spoiler, a magnet for protest votes, and a significant pressure point on the Liberals’ right flank.
This is where the Thucydides analogy becomes useful.
The Liberal Party is not facing a single clean challenge from Labor. It is dealing with pressure from two directions at once. Labor is the external competitor. One Nation is the insurgent force pulling at the edge of the party’s traditional coalition. That combination makes the Liberal problem look like a structural crisis.
The internal divisions make it worse. The Liberals have been plagued by factional conflict, in NSW and Victoria, and relegated to ‘phone-box’ size in SA and WA. That electoral failure is further amplified by the fragile nature of the coalition, that acts like teenagers on their second date.
In practical terms, this means the party is trying to solve a political problem while fighting itself at the same time. One faction wants to reclaim the centre. Another wants to sharpen the message and move further right. A third is mostly concerned with survival, which is often the most dangerous faction of all, because it mistakes tactical retreat for strategy.
The result is familiar to anyone who has watched a declining institution under stress. The more pressure it feels, the more defensive it becomes. The more defensive it becomes, the more it narrows its appeal. Inevitably, the narrower its appeal becomes, the harder it is to recover the trust of voters who have already started looking elsewhere.
There is also a deeper identity problem. One Nation is not simply another competitor; it is a party that speaks directly to voters frustrated by elites, suspicious of moderation, and impatient with compromise. That puts the Liberals in a bind. If they move too far right, they risk alienating urban moderates and business-oriented voters. If they move back to the centre, they risk losing more ground to the hard right.
That is the political version of the Thucydides trap. The rising challenger forces the established party into a reactive posture, and the fear of losing ground produces increasingly unstable choices. In Thucydidean terms, the rise of the challenger creates anxiety in the incumbent, and that anxiety begins to shape every response.
Of course, the analogy has limits. No political party is Sparta, and no election is the Peloponnesian War. The point is not that the Liberals are doomed, or that history repeats itself in a literal sense. The point is that dominant institutions often struggle most when they lose the confidence that once held their coalition together.
That is where the Liberal Party now seems to be. It is no longer the natural party of government on the centre-right. It is a party trying to decide whether it wants to chase the middle, absorb the right, or somehow do both at once. That is a very hard balancing act when the ground beneath you is shifting.
So, has the Liberal Party fallen into the Thucydides Trap?
Yes.
A once-dominant force has fragmented and risks becoming increasingly irrelevant at a time when we need a competent, cohesive opposition able to put aside partisan nonsense for the benefit of the country.
Header Thucydides: courtesy Wikipedia.
