The Changing International Political Order
The system has run through bipolarity, a unipolar interval and an unsettled present. The useful question is not what to call the present but which of the unipolar moment’s institut…
The system has run through bipolarity, a unipolar interval and an unsettled present. The useful question is not what to call the present but which of the unipolar moment’s institutions still command consent.
This is chapter 41 of the PSIR Optional Notes, from the part on International Relations in the Paper II syllabus. The complete book is a free download.
UPSC syllabus
Changing International Political Order: rise of superpowers, strategic and ideological bipolarity, arms race and Cold War, nuclear threat; Non-aligned movement: aims and achievements; collapse of the Soviet Union, unipolarity and American hegemony, relevance of non-alignment in the contemporary world.
In one page
- The Cold War was strategic and ideological at once: a bipolar distribution of capabilities and a contest between two universalist models of social order.
- Its architecture: the Truman Doctrine and containment (1947), the Marshall Plan, NATO (1949) and the Warsaw Pact (1955), and a nuclear arms race that passed through massive retaliation, flexible response and mutual assured destruction.
- The Cold War’s origins are contested between orthodox, revisionist and post-revisionist historiographies, and naming the debate is worth marks.
- Détente in the 1970s produced SALT I, the ABM Treaty and the Helsinki Final Act; the Second Cold War followed from 1979.
- The Soviet collapse in 1991 had structural causes, economic stagnation, imperial overstretch, the failure of perestroika and glasnost to be sequenced, and nationality pressures.
- The unipolar moment produced expansive American primacy, humanitarian intervention, and its own overextension in Iraq and Afghanistan.
- The present order is variously described as multipolar, non-polar, multiplex (Acharya) or unbalanced multipolarity. What is agreed is that the United States remains the strongest single power without being able to set outcomes alone.
- Constraints on American hegemony, asked in 2023, are external (China, Russia, middle powers, institutional resistance) and internal (fiscal, political polarisation, war fatigue), and the internal are now the more binding.
The Cold War
Origins and the historiographical debate
Orthodox accounts place responsibility on Soviet expansionism and the ideological drive to extend communism; the imposition of regimes in Eastern Europe is the evidence. Revisionist accounts, from Williams and Kolko, place it on American economic expansionism and the search for open markets, with the atomic bombings read as directed partly at Moscow. Post-revisionist accounts, principally Gaddis, treat it as a security dilemma in which each side’s defensive measures appeared offensive to the other, with the power vacuum in Central Europe as the precipitant. The last is the standard scholarly position and the safest to adopt while naming the others.
Architecture and phases
- 1947–53, formation. Truman Doctrine (March 1947) and Kennan’s containment; Marshall Plan (1947); Berlin blockade and airlift (1948–49); NATO (1949); Soviet atomic test (1949); Chinese revolution (1949); Korean War (1950–53); NSC-68’s militarised containment.
- 1953–62, confrontation and crisis. Warsaw Pact (1955); Hungary (1956); Suez (1956); Sputnik (1957); U-2 (1960); Berlin Wall (1961); Cuban missile crisis (1962), the closest approach to nuclear war and the trigger for the hotline and the Partial Test Ban Treaty (1963).
- 1962–79, détente. Nuclear Non-Proliferation Treaty (1968); SALT I and the ABM Treaty (1972); Helsinki Final Act (1975) with its human rights basket, which proved consequential; Sino-American rapprochement from 1971–72, which is the pivotal strategic event of the period.
- 1979–85, second Cold War. Soviet intervention in Afghanistan (1979); the Euromissile crisis; the Strategic Defense Initiative (1983).
- 1985–91, ending. Gorbachev’s glasnost, perestroika and new thinking; INF Treaty (1987); withdrawal from Afghanistan (1989); the East European revolutions (1989); German unification (1990); dissolution of the USSR (December 1991).
The nuclear dimension
Doctrinal evolution: massive retaliation under Dulles, criticised for offering only capitulation or holocaust; flexible response from Kennedy, adding conventional and limited nuclear options; assured destruction and then mutual assured destruction once both sides had survivable second-strike forces.
Arms control: Partial Test Ban 1963, NPT 1968, SALT I and ABM 1972, SALT II 1979 (signed, not ratified), INF 1987, START I 1991 and START II, CTBT 1996 (not in force), New START 2010. The recent direction is erosion: the United States withdrew from the ABM Treaty in 2002 and both parties from the INF Treaty in 2019, and the arms-control architecture is now thinner than at any time since the 1960s.
Non-alignment
Treated fully in Chapter 47 from India’s standpoint. What belongs here is its systemic role. Non-alignment emerged from Bandung (1955) and was institutionalised at Belgrade (1961) under Nehru, Tito, Nasser, Sukarno and Nkrumah. Its systemic significance: it denied both blocs the automatic adherence of the newly independent states; it created a diplomatic space in which decolonisation, disarmament and economic justice could be pressed; and it supplied the numbers that made the General Assembly a forum for Southern demands, including the NIEO of 1974.
Its limits: internal divergence, since members ranged from genuinely equidistant to closely aligned; the failure to prevent conflicts among members; and the loss of its organising rationale when one pole disappeared.
The Soviet collapse and the unipolar moment
Why the USSR collapsed
- Economic. Growth stalled from the 1970s; the command economy could not manage complexity or innovation; military spending consumed a very large share of output; oil revenues fell in the mid-1980s.
- Imperial overstretch. Afghanistan, subsidies to Eastern Europe, Cuba and Vietnam, and the cost of matching American technological programmes.
- Reform sequencing. Glasnost preceded and outpaced perestroika: political opening released nationality and reformist pressures before economic restructuring had produced any gains, so the system lost legitimacy without delivering results.
- Nationalities. The federal structure gave union republics institutions and borders that became the vehicles of secession.
- Ideological exhaustion and, decisively, the abandonment of the Brezhnev Doctrine, which told Eastern European regimes they would not be rescued.
Unipolarity and its critics
Charles Krauthammer named the unipolar moment in 1990–91; Fukuyama‘s end of history (1989) gave it an ideological reading; Wohlforth argued unipolarity was durable because the gap was too large to balance against. Against that, Waltz predicted balancing would follow, and Huntington argued the clash of civilisations would define the coming order, and that the system was better described as uni-multipolar.
American primacy in practice: the Gulf War of 1990–91 as collective security’s clearest success; humanitarian intervention in the 1990s with Somalia, Bosnia, Rwanda’s failure and Kosovo; NATO enlargement; the WTO; and after 2001 the global war on terror, Afghanistan and the 2003 invasion of Iraq, which was undertaken without Security Council authorisation and became the turning point in legitimacy.
Constraints on American hegemony
The 2023 paper asked which constraints exist and which are likely to grow, so the answer must separate the two.
| Present constraint | Trajectory | |
|---|---|---|
| External: China | Economic scale approaching parity; military modernisation; technological competition; Belt and Road as an alternative infrastructure of influence | Rising; the most consequential single constraint |
| External: Russia | Nuclear parity, energy leverage, willingness to use force, and the Ukraine war as a test of Western cohesion | Reduced conventionally, undiminished as a disruptive power |
| External: middle powers | India, Brazil, Turkey, Gulf states, Indonesia, all hedging rather than aligning; BRICS and its expansion | Rising; the multi-alignment pattern of Chapter 46 |
| External: institutions and norms | Legitimacy costs of unilateral action; Security Council constraint; declining appetite for intervention | Stable |
| Internal: fiscal | Debt burden, entitlement pressure, competing domestic claims on the budget | Rising |
| Internal: political | Polarisation, contested foreign-policy consensus, reduced predictability across administrations | Rising, and now the most binding |
| Internal: societal | War fatigue after Iraq and Afghanistan; reluctance to accept casualties | Stable to rising |
The judgement to offer: the external constraints are real but the binding constraint is domestic willingness. Material preponderance persists, in military reach, the dollar, and technological frontier capacity; what has eroded is the political consensus to underwrite an order, which is why the 2025 paper’s question about allies being told to invest in their own defence belongs here.
The present order
The competing descriptions, and an answer should choose one with reasons rather than list them.
- Multipolar: several great powers, none preponderant. Accurate about economic weight, less so about military reach, where the asymmetry remains very large.
- Non-polar (Haass): power diffused among states, corporations, NGOs, cities and networks, with no concentration at all.
- Multiplex (Acharya): the standard formulation to know. The order after American primacy is not a return to nineteenth-century multipolarity but a world with multiple modernities, multiple regional orders, overlapping institutions and complex interdependence, like a multiplex cinema running several films at once with no single showing.
- Unbalanced multipolarity or partial unipolarity: the United States remains first among unequals but cannot determine outcomes alone.
The observable features: the return of great-power competition; weaponised interdependence, in Farrell and Newman’s term, where networks of finance, data and supply become instruments of coercion; minilateralism, the Quad, AUKUS, I2U2, IPEF, in place of universal institutions; regionalisation of security; and contested rather than shared norms.
Where answers lose marks
- Narrating the Cold War as a chronology. The question is usually analytical, and phases plus the historiographical debate are worth more than dates.
- Attributing the Soviet collapse to a single cause. Economic stagnation, overstretch, reform sequencing and nationalities all contributed, and the abandonment of the Brezhnev Doctrine was the proximate trigger in Eastern Europe.
- Declaring the order simply multipolar. Economic weight is distributed; military reach and the dollar are not. Say which dimension you mean.
- Omitting Acharya’s multiplex world. It is the formulation examiners increasingly expect from a non-Western vantage.
- Treating constraints on American power as purely external. Fiscal and political constraints are now the binding ones.
Asked before
- Discuss the various constraints on American hegemony today. Which of these are likely to become more prominent in the future? (2023, Paper II, 15 marks)
- Do you agree with the view that the USA uses NATO as a traditional tool of strategy to perpetuate its hegemony in the world? (2024, Paper II, 15 marks)
Answer skeleton
Discuss the various constraints on American hegemony today. Which of these are likely to become more prominent in the future? (15 marks, 250 words)
Frame. Distinguish capability from willingness at the outset. American material preponderance has eroded less than its political capacity to convert preponderance into outcomes.
External constraints. China’s economic scale, military modernisation and technological competition, with Belt and Road as an alternative infrastructure of influence. Russia’s nuclear parity and willingness to use force. Middle powers, India, Brazil, Turkey, the Gulf states, hedging rather than aligning, and BRICS expansion. Institutional and legitimacy costs, sharply raised after Iraq in 2003.
Internal constraints. Fiscal pressure and debt; political polarisation making foreign policy unpredictable across administrations; and societal war fatigue after Afghanistan and Iraq.
Which will grow. The internal ones, and China. Polarisation reduces the credibility of commitments, which is the currency of alliance; fiscal pressure competes with defence and aid; and China’s constraint compounds as its economy and technology mature. Russia’s conventional constraint has diminished while its disruptive capacity has not.
Which will not. Institutional constraint is stable rather than rising, since the same United States that is constrained by institutions can also bypass them, as 2003 showed.
Conclude. Hegemony is being replaced not by another hegemon but by Acharya’s multiplex order: multiple regional orders, overlapping institutions and no single power able to set outcomes, in which the United States remains the strongest single actor without being the organiser of the system.
Last-mile revision
- Historiography: orthodox, revisionist (Williams, Kolko), post-revisionist (Gaddis).
- Phases: 1947–53 formation; 1953–62 crisis; 1962–79 détente; 1979–85 second Cold War; 1985–91 ending.
- Landmarks: Truman Doctrine 1947, Marshall Plan 1947, NATO 1949, Warsaw Pact 1955, Cuban missile crisis 1962, PTBT 1963, NPT 1968, SALT I and ABM 1972, Helsinki 1975, INF 1987, START I 1991.
- Doctrine: massive retaliation, flexible response, MAD. Erosion: ABM withdrawal 2002, INF collapse 2019.
- Soviet collapse: economic stagnation, overstretch, glasnost outpacing perestroika, nationalities, abandonment of the Brezhnev Doctrine.
- Unipolarity: Krauthammer 1990–91, Fukuyama 1989, Wohlforth’s durability, Waltz’s balancing prediction, Huntington’s uni-multipolar and clash of civilisations.
- Present: multipolar, non-polar (Haass), multiplex (Acharya), unbalanced multipolarity; weaponised interdependence; minilateralism.
Read the rest. This chapter is one of 58 in the complete PSIR Optional Notes, covering Paper I and Paper II in full — free to download.