by PETER TOFT
The world is currently experiencing an extraordinary period of turmoil and upheaval, including war in Ukraine, multiple inter-state conflicts in the Middle East, mounting doubts about NATO’s future, and a global surge of anti-democratic tendencies. This is not just about the leaders of major powers like Trump, Putin, or Xi; it is about a profound shift in the international power structure—from American unipolarity to an emerging bipolarity between the U.S. and China. In a recent article in the Journal of Regional Security, I developed an interpretation of this transition based on neorealist theory of international politics. I also outlined four predictions about how the transition will shape international politics in the coming years.
From American Hegemony to Two Superpowers
After the Cold War, international politics was often described as operating under a liberal, rules-based order led by the United States. I view this period as a highly unique and always a temporary “unipolar moment”: a phase in which the United States enjoyed unrivaled military and economic power and could dominate the global agenda.
However, as many observers now agree, the unipolar moment has ended. More debated is what has replaced it. Increasingly, the picture looks like a new kind of bipolarity, with the United States joined by China at the top. This bipolar balance of power does not require perfect parity. The United States remains the stronger player, but as Jennifer Lind notes, it no longer stands head and shoulders above everyone else. China now serves as a rough counterweight. This emerging structure is reinforced by the considerable distance between these two and all other powers. As Øystein Tunsjø has shown, the United States and China enjoy a clear lead, far ahead even of Russia. Thanks to China’s extraordinary economic and military rise, we now have two states capable of offering security guarantees and key economic benefits to others. Both increasingly compete fiercely in security and trade to shape the future of international politics – creating new tensions, alignments, and lines of conflict.
Why It’s Not Just About Trump, Xi, and Putin
However, in public discourse, current global disorder is often explained in terms of individual leaders: Trump, Putin, Xi, and others. Neorealist theory, most closely associated with Kenneth Waltz, reminds us that leaders internationally operate within a broader structural framework that both shapes and constrain their freedom of action. (For a more accessible introduction to Waltz’s thinking, see this interview.)
Leaders are constrained by the international structure, which is anarchic – that is, lacking an overarching authority capable of enforcing rules or guaranteeing security should others threaten them with military action. To survive and prosper, states are therefore left to fend for themselves as best they can – mobilizing their own resources and in cooperation with others. Smaller states, in particular, often depend on superpowers for security and strategic backing. During the unipolar moment, the United States was the sole superpower – its unmatched power made it the only credible guarantor of security and allowed it to deter or punish most challengers. That era, however, is fading. As China’s ascent chips away at U.S. primacy, the familiar anchors of the unipolar order are loosening. With China increasingly able to pose a direct challenge to U.S. supremacy, especially in East Asia, uncertainty is spreading over how the superpowers will define their relations, manage flashpoints, and set their regional priorities – leaving the international system in a fluid and fragile transitional phase.
Four trends to expect with the shift in the international system are as follows:
The article outlines four expectations about how periods following profound shifts in global power influence international politics.
- The risk of conflict increases.
When power dynamics are in flux and the relative strength of states is unclear, the risk of armed conflict tends to rise. States that face growing uncertainty about whether their allies will support them have incentives to rearm, shift alliances, or launch preventive strikes – steps that others can easily interpret as threatening. Likewise, states that find themselves in a temporarily stronger position relative to a rival may be tempted to secure a better long-term position by acting while a window of opportunity still exists. Recent and ongoing conflicts such as the war in Ukraine, the war between Armenia and Azerbaijan, the fighting in and around Gaza, and the escalating Israeli–U.S. confrontation with Iran fit into a historical pattern of multiple interstate conflicts concentrated during periods of systemic transition. Historical parallels can be found in the years following both World War I and World War II, as well as after the Cold War, when the international system experienced a sharp increase in conflict outbreaks.
- Alliances are in flux, and new partnerships are forming.
Systemic transformation also drives shifts in alliances, especially for states that have relied on an increasingly uncertain or declining superpower ally. Examples of this include European discussions about their dependence on U.S. security guarantees, Sweden’s and Finland’s NATO membership, and new recent and strengthening defense agreements in the Pacific and Indo-Pacific regions. Alliances are becoming more fluid, and “old truths” about who stands together can change quickly. Again, historical parallels can be found in the 1920s, late 1940s, and 1990s, when international alliances dissolved and new ones formed rapidly.
- Emergence of new states and increased risk of old ones collapsing.
Historically, as noted by, Birthe Hansen, periods of global systemic transformation – such as those following World War I, World War II, and the Cold War – tended to coincide with the formation of new states and the collapse of internally weaker ones. As great powers reprioritize and shift their focus, new opportunities can emerge for national independence movements to push for secession and redraw borders. At the same time, state disintegration becomes more likely when external backing erodes or disappears. In the current transition, we have not yet seen a comparable wave of new state formation, though the structural preconditions appear increasingly favorable.
- From a wave of democratization to a counter-wave of de-democratization
Previous analyses, for example by Samuel Huntington, have shown that the post–Cold War era witnessed a massive wave of democratization under the emergence of a U.S.-led unipolar order. Today, however, we are witnessing the reverse trend: a democratic decline across most world regions, as shown by indices such as V‑Dem, Freedom House, and the Economist Intelligence Unit. I argue that this development is closely linked to the current transition toward bipolarity. In this evolving landscape, an authoritarian, state‑controlled Chinese model of governance is emerging as an alternative path to economic development, and national security. At the same time, the incentive to emulate the United States has weakened due to its relative loss of power and deep internal polarization. With a rival superpower once again in the system, the U.S. – with or without President Trump at the helm – is also less inclined to promote democracy abroad and more focused on curbing China’s rise, even if that requires cooperation with less appealing partners, as was common during the Cold War.
Implications and Next Steps
Viewing the current global turmoil through a systemic‑structural lens has two key implications. First, it reminds us that much of the instability in the 2020s is not simply the result of “bad leaders” or isolated events, but an expected outcome of profound global power shifts. Second, it suggests that policymakers should plan for a prolonged period of uncertainty, intensified security competition, and a more fragmented alliance landscape – one that may feature new, potentially unstable states and a growing number of undemocratic regimes.
While my article is primarily theoretical and conceptual, it lays the groundwork for systematic empirical testing of the four propositions outlined earlier about how systemic transitions unfold. We have at least four recent historical examples of such global transformations – the 1920s, the late 1940s and early 1950s, the 1990s, and now the 2020s – offering an opportunity for comparative analysis across these periods and the structurally more stable intervals between them. The broader goal is to develop more effective tools for understanding, anticipating, and mitigating the most contentious dynamics of systemic change. Recognizing these patterns is essential not only for explaining today’s turbulence but also for preparing policy responses that manage systemic change.
Peter Toft is an independent scholar from Denmark and a director in country risk. His current research focuses on international relations theory, especially realist theories and how they can deepen our understanding of the shifting world order away from unipolarity.
Cover image credit: Pexels, Lara Jameson
You can also read:
“From unipolarity to bipolarity: Systemic transformation and the emergence of post-unipolar international politics,” by Peter Toft, Journal of Regional Security, 20 (2): 209-238 (2025).
