IB DP Global Politics – Core topic – Theoretical perspectives in global politics Study Guide

This study guide teaches the core topic “Theoretical perspectives in global politics” for IB Diploma Programme Global Politics. It follows the IB Diploma Programme Global politics guide (first assessment 2026, published February 2024), the course examined from the May 2026 session onwards. The topic sits in the core, “Understanding power and global politics”, which is the same for SL and HL, so everything here applies at both levels.

Use it with the revision notes for this topic and the practice questions. For the whole course, see the IB DP Global Politics hub, the printable checklist and the syllabus guide.

What this unit covers

The guide says no particular political theory is prescribed content. It strongly encourages teachers to cover a range, and names five: realism, liberalism, and three critical theories – feminism, postcolonialism and social constructivism. What is prescribed is the skill of using theory.

Prescribed content	What you must be able to do	SL/HL
Theories, models and analytical frameworks in global politics	Explain what a theory, a model and a framework are, and set out the main assumptions of the five perspectives the guide names	SL and HL
Use and applicability of theories and models to political issues	Apply a perspective to a real case: organise evidence, explain causes, consequences and motives, predict, and prescribe	SL and HL
Bias and limitations of theories and models	Judge where a theory works, where it fails, and whose viewpoint it reflects	SL and HL

Theories, models and frameworks

A theory is a set of linked assumptions that claims to explain how politics works.

A model is a simplified picture of one part of politics, often a set of categories. The hard, soft and smart power classification in the core is a model: it sorts types of power without telling you why states choose them.

An analytical framework is a structured way of asking questions of a case. Looking at an issue at different scales – global, regional, national, local – is a framework the guide itself uses.

The guide lists what these tools do. In plain terms:

• Organise – sort a mass of facts into a pattern.
• Simplify – pick out what matters and leave out detail.
• Explain – give causes, consequences and motives.
• Predict – say what is likely to happen next.
• Prescribe – say what actors should do.
• Evaluate and critically review – test claims, including other theories.

Realism and liberalism are mainly explanatory. The critical theories also ask whose interests a way of seeing serves.

The five perspectives

Realism

Realists start from anarchy: there is no authority above states. Each state must rely on itself to survive (self-help). States are the main actors, and they pursue the national interest, defined largely as security. Military and economic capability decide outcomes. Classical realists such as Hans Morgenthau linked this to human nature. Structural realists such as Kenneth Waltz (Theory of International Politics, 1979) put it down to the structure of the system. John Mearsheimer, named in the guide’s power section, argues that great powers seek to maximise their relative power.

Two ideas you should be able to use:

• Security dilemma – when one state arms for defence, others see a threat and arm too, so everyone ends up less safe.
• Relative gains – states care about how much they gain compared with rivals, which makes cooperation fragile.

Liberalism

Liberals accept that anarchy exists but argue that cooperation is possible and common. States and many other actors (IGOs, companies, NGOs) seek absolute gains: a deal is worth making if you are better off, even if a partner gains more. Institutions reduce cheating by sharing information and setting rules. Robert Keohane and Joseph Nye’s Power and Interdependence (1977) describes complex interdependence, where many channels link societies and military force becomes less useful. Democratic peace theory holds that established democracies rarely, if ever, fight each other.

Social constructivism

Constructivists argue that ideas, identities and norms shape what states want. Interests are not fixed by material power alone. Alexander Wendt’s 1992 article “Anarchy is what states make of it” makes the point that anarchy means different things between friends and between rivals. Norms change, often through norm entrepreneurs. The International Campaign to Ban Landmines helped bring about the 1997 Ottawa Treaty banning anti-personnel mines, and shared the Nobel Peace Prize that year.

Feminism

Feminist perspectives make gender a category of analysis. They ask where women are in global politics and how ideas of masculinity shape security, war and the economy. Cynthia Enloe’s Bananas, Beaches and Bases traced women’s roles around military bases, plantations and diplomacy. Feminists widen “security” to include the safety of people, not only of states. UN Security Council Resolution 1325 (2000) on women, peace and security is a key reference point. There are several strands – liberal, critical and postcolonial feminism among them – so avoid treating feminism as one view.

Postcolonialism

Postcolonial perspectives study how colonialism still shapes the world: borders, economic ties, institutions and ways of thinking. Edward Said’s Orientalism (1978) showed how Western writing built images of “the East” that justified control. Postcolonial scholars argue that mainstream theory was built from European and North American experience and then treated as universal. Walter Mignolo, named in the guide’s power section, writes on decoloniality. These perspectives stress the agency and viewpoints of the Global South.

How each perspective reads the key concepts

The four key concepts run through the whole course, and each has its own guide: power, sovereignty, legitimacy and interdependence. This table shows how each lens reads them.

	Power	Sovereignty	Legitimacy	Interdependence
Realism	Material capability, mainly military; relative	Central; the basis of the state system	Follows effective control; secondary to security	Creates vulnerability; states limit dependence on rivals
Liberalism	Spread across many actors; soft power matters	Can be pooled or limited by agreement (e.g. EU)	Comes from consent, law and democratic process	Raises the cost of war and encourages cooperation
Constructivism	Includes power over ideas and meanings	A social institution whose meaning changes	Depends on shared norms and recognition	Shapes identities; repeated cooperation builds trust
Feminism	Often “power over”; asks about “power with”	State control can hide harm in private life	Questioned where women are excluded from decisions	Global supply and care chains rest on gendered labour
Postcolonialism	Built on historical hierarchy	Often limited in practice for former colonies	Global institutions judged by who holds seats and vetoes	Can mean dependency, e.g. reliance on commodity exports

A constructivist example on sovereignty: at the 2005 World Summit, UN member states endorsed the Responsibility to Protect (R2P). It recast sovereignty as including a duty to protect a population from mass atrocities. For a constructivist this shows a norm changing what sovereignty means. For a realist, the fact that R2P is applied selectively shows that power still decides.

Worked example: one case, five lenses

Case: the 2015 Paris Agreement on climate change. Each party sets its own nationally determined contribution (NDC) to cut emissions.

Step 1 – state the issue. Why did almost every state join an agreement that lets each one set its own target?

Step 2 – apply each perspective.

• Realism: states protected sovereignty and economic power. Self-set targets meant no state was bound to a level that would weaken it against rivals.
• Liberalism: the agreement is an institution that builds cooperation over time. Regular reporting and review make free-riding visible, and every state gains from a stable climate.
• Constructivism: climate action became a norm of responsible statehood. States joined partly because staying out damaged their identity and reputation.
• Feminism: asks who decides and who bears the cost. Women’s representation in delegations, and the gendered effects of climate shocks on unpaid care and food work, fall outside a state-only lens.
• Postcolonialism: stresses historical emissions. The principle of common but differentiated responsibilities, set out in the 1992 UN Framework Convention, and the loss and damage fund agreed at COP27 in 2022 reflect claims by states that emitted little but suffer most.

Step 3 – evaluate. Realism explains why targets are voluntary; liberalism why states keep reviewing them; the critical theories who is missing. Saying which lens explains which part is the evaluation.

Bias and limitations

Every theory simplifies, so every theory leaves something out. Ask four questions.

1. What is the unit of analysis? Realism looks at states. It struggles with a social movement or a company that shapes policy.
2. Can it explain change? Structural realism predicts continuity. It found it hard to account for the Cold War ending without a great-power war. Constructivism explains change well but often only after it has happened.
3. Does it predict? Realism and liberalism make testable predictions. Constructivism, feminism and postcolonialism are stronger at uncovering assumptions than at forecasting.
4. Whose view does it reflect? Postcolonial and feminist critics argue that realism and liberalism grew out of the experience of powerful Western states and men. Liberals reply that their claims about institutions and trade are tested across many regions.

A theory can also shape behaviour. If leaders believe rivals are always hostile, they may act in ways that make rivalry more likely. This self-fulfilling risk is a limitation worth using in essays.

Using theory in the exams

Paper 1 (1 hour 15 minutes, 25 marks, SL and HL) is source-based and draws on the core topics, so theory can appear here. The last question rewards evaluating sources, synthesis with your own knowledge, and exploring and evaluating different perspectives. Recognising that a source reasons like a realist or a liberal is a quick way to show this.

Paper 2 (1 hour 45 minutes, 30 marks, SL and HL) asks for two essays. One comes from section A, on a thematic study, and one from section B, whose integrating questions connect the thematic studies and the core. The top markband expects diverse perspectives that are explored and evaluated. Theory is one strong way to do that.

A theory paragraph has four parts:

1. Claim – the perspective’s argument about the question.
2. Case – a specific, developed example.
3. Link to a key concept – power, sovereignty, legitimacy or interdependence.
4. Limit – what the perspective misses, and which other lens covers it.

Worked paragraph (Paper 2, integrating question on cooperation during health crises):

A realist reading expects states to protect their own populations first. During the COVID-19 pandemic several states restricted exports of vaccines or medical supplies, which fits the realist view that sovereignty and national interest override cooperation under pressure. Yet the COVAX facility, launched in 2020, pooled funding to share vaccines more widely, which liberals would cite as institutions softening self-help. A postcolonial lens adds that lower-income states waited longest, so the question is not only whether states cooperated but on whose terms.

It names a perspective, uses a real case, links to key concepts and turns to other lenses.

Common errors

• Listing theories without a case. Five definitions earn little. One case seen through two or three lenses earns more.
• Treating constructivism as idealism. Constructivism says ideas shape interests. It does not say states are kind.
• One-word feminism or postcolonialism. “Feminists would disagree” is not analysis. Say what they would ask and why.
• Treating theories as facts. Write “a realist would argue”, not “states always act selfishly”.
• Using only historical cases. The guide treats contemporary as roughly the last two decades.
• Forgetting evaluation. Every perspective you use needs a limit, or you stay out of the top markband.

Next steps

Condense this with the revision notes, then try the practice questions. For paper structure, see the assessment revision notes. To test lenses on thematic content, use the peace and conflict and rights and justice study guides.

Official syllabus

International Baccalaureate Organization, Diploma Programme Global politics guide, first assessment 2026 (published February 2024). Core topics: “Understanding power and global politics” – prescribed topic “Theoretical perspectives in global politics”.