Research

My research mostly engages questions at the intersection of political psychology, foreign policy, public opinion, and international security. The unifying theme is an interest in how decision makers and the public interact. I have pursued this interest in the following fields (for more information, see below):

Public opinion, domestic politics and international relations
European (EU) foreign and security ingration
National identity
Political communication, electoral choice and turnout

For a list of my publications sorted by year, see the Publications page on this website or my Google Scholar Profile.

Public opinion, domestic politics and international relations

How do citizens form attitudes toward foreign policy issues? Understanding public opinion in this area is important for assessing the democratic legitimacy of foreign policies and because public opinion influences elite behavior and decision making. To avoid jeopardizing their popularity ratings, democratic governments pay attention to public opinion, in particular when issues are politicized, i.e. when they are salient and contested in domestic politics.

My work in this field focuses on how general postures and context-specific beliefs interact in shaping attitudes toward specific foreign policies, including collective defence, military interventions, arms deliveries and economic sanctions (here). I have (co-)authored two books on these topics (here and here) as well as numerous journal articles, which have appeared in leading outlets such as the European Journal of Political Research (here), Journal of Conflict Resolution (here), Review of International Political Economy (here), and Public Opinion Quarterly (here).

German Foreign Policy Panel

I am co-director of the the German Foreign Policy Panel (GEFOP), which started in May 2025 with the goal to analyze stability and change in German public opinion on foregin policy. This project examines German public opinion on foreign and security policy amid profound global change and increasing domestic politicization driven by the war in Ukraine and the second term of U.S. President Trump. By conducting a multi-wave panel survey and linking these data to existing sources, the project tracks different types of public orientations and their interrelationships, ranging from immediate perceptions of threats and preferred policy measures to deeper predispositions, such as country images and foreign policy postures. Understanding these opinion dynamics is crucial, as public attitudes shape democratic decision-making and international policy choices. Beyond its timeliness, the project provides a unique opportunity to examine fundamental questions about the stability and evolution of foreign policy attitudes, offering insight into how and when public opinion adapts to a shifting global landscape.

Project status: Wave 1 (N=6,000) completed.

Recent publications

Mader, Matthias. 2024. Increased support for collective defence in times of threat: European public opinion before and after Russia’s invasion of Ukraine. In: Policy Studies, 45(3-4), 402-422.

Mader, Matthias, Harald Schoen. 2023. No Zeitenwende (yet): Early Assessment of German Public Opinion Toward Foreign and Defense Policy After Russia’s Invasion of Ukraine. In: Politische Vierteljahresschrift, 64, 525-547.

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A public mandate for European defence ingration?

The area of foreign and security policy remains one if the least integrated policy areas in the European Union. Is the slow progress of integration a result of the reluctance of elites rather than to the reticence of Europe’s citizens? My research on this question is includes the analysis of public opinion dynamics (here) and how citizens react to international threat (here) and the costs of cooperation (here). A key interest is whether high levels of support for European integration in the defence domain, as usually measured in surveys such as the Eurobarometer, reflect a public mandate or rather shallow opinions likely to crumble in the face of costs.

The SecEUrity Project

In collaboration with a large group of European scholars I currently conduct a research project titled “Fighting together, moving apart? European common defense and shared security in an age of Brexit and Trump.” The project studies the dynamic relationship between elites and masses in policy-making about common defense in the multi-level European system and is generously funded by the Volkswagen Stiftung. Visit the project’s website (secEUrity.eu) for more information.

Project status: Data collection completed.—

Recent publications

Mader, Matthias, Moritz Neubert, Felix Münchow, Stephanie Hofmann, Harald Schoen, Konstantin Gavras. 2024. Crumbling in the face of cost? How cost considerations affect public support for European security and defence cooperation. In: European Union Politics 25(3), 483-503.

Mader, Matthias, Konstantin Gavras, Stephanie Hofmann, Jason Reifler, Harald Schoen, Catarina Thomson. 2024. International threats and support for European security and defence integration: Evidence from 25 countries. In: European Journal of Political Research, 63(2), 433-454.

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National identity

In the age of globalization, national boundaries become both permeable and contested. Processes of international cooperation and migration cross and highlight national borders and have the potential to invoke national identity as a force that drives citizens’ opinion formation toward a wide range of issues. Conceptions of national identities come in different forms—there is variation between individuals and across time and space—and have distinct effects on political attitudes and behavior. I have pulished widely on these issues, including the question of stability and change of national identity (here and here), its relationship with foreign and domestic policy preferences (e.g., here and here) and political behavior (here and here).

Completed project

Citizens’ Multidimensional National Identities and Foreign Policy Attitudes in Different Contexts (2017 to 2021): Research project funded by the Mannheimer Zentrum für Europäische Sozialforschung (MZES). For more information, visit the MZES project website.

Recent publication

Mader, Matthias, Harald Schoen. 2023. Stability of national identity content: level, predictors, and implications. In: Political Psychology. Early View.

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Political communication, electoral choice and turnout

Electoral behvior is the result of a complex interplay of party politics, political discourse about them, and voters’ predispositions. My work in this field has considered the relevance of a range of such predispositions for political participation in different contexts, including the relevance of political values and postures (here and here), ideological attachments (here), and national identities (see above). In a recent article on the effects of immigration attitudes on vote choice (here), Harald Schoen and I show how German citizens responded to party behaviour by changing partisan preferences on the basis of prior immigration attitudes in the context of the so-called refugee crisis in 2015. This event may thus have been a critical juncture transforming party competition in Germany.

I am also interested in how political communication influences citizen attitudes and behavior. My research focuses on the degree to which different elite actors can shift opinion in different sections of the general population. What are messages that ‘work’, in the sense of moving policy attitudes of targer audiences, and to what degree do such effects vary as a function of individual differences? And can anyone shape public opinion, or are there differences in who citizens are willing to listen to? My research addresses these questions from various angles. Prior publications have focused on differential framing effects on attitudes toward military action (here), on the capacity of interest group communication to change public opinion on issues ranging from free trade to sustainable energy transition (here), and on the vulnerability of different segments of democratic societies for believing foreign hybrid propaganda (here).