In the wake of its invasion of Ukraine, the Russian government has carried out a large-scale crackdown against citizens perceived as opposing the war. Russian President Vladimir Putin made his intentions clear in a speech in March, warning that the West “will try to bet on the so-called fifth column, on traitors—on those who earn their money here, but live over there. Live, not in the geographical sense, but in the sense of their thoughts, their slavish thinking.”

Putin’s rhetoric has been translated into official policy: dissidents and independent-minded Russians have been accused of advancing Western interests and working to undermine Russia from within. Some have been fined, imprisoned, or tortured. This campaign against supposed traitors has been mounted not only by the Kremlin’s agents directly but also by ordinary citizens who believe they are acting patriotically by turning on their neighbors and colleagues. The playbook is one that leaders are using in a growing number of countries, identifying and vilifying domestic groups purportedly working with external enemies to undermine the national interest—and then inciting the public to target them. In so doing, these leaders exploit preexisting prejudices, national security fears, and geopolitical rivalries to weaken domestic political opponents and boost the cohesion of “insiders” who support them.

Although the term “fifth column” wasn’t coined until the 1930s, the practice of identifying and targeting such threats is a far older phenomenon and arguably predates the nation-state. For much of history, governments have mostly dealt clandestinely with fifth columns rather than trumpet their presence for political gain. In recent years, however, there has been a notable rise in political rhetoric about fifth columns around the world. This increase is attributable to several converging factors: rising geopolitical instability, which increases the likelihood that countries will meddle in the internal affairs of their rivals; the spread of nationalism as a common-sense belief, which reinforces the resonance of fifth-column claims; the electoral success of populist and ethnonationalist movements that often trumpet such concerns; and the widespread adoption of social media, which facilitates the rapid diffusion of fifth-column rhetoric. As long as these trends persist, the focus on externally backed “enemies within” will intensify. Fifth columns, real or imagined, will shape not just the internal politics of many countries but relations among them as they struggle for dominance on the international stage.


Suspicion that insiders are undermining the national interest can stem from an ideology such as Putin’s or from an ethnic, cultural, or religious identity that marks a group as distinct from the national majority and therefore suspect. Which of these criteria matters most has depended on the larger anxieties and geopolitical dynamics of the era.

The first half of the twentieth century saw a focus on ethnically defined fifth columns as Europe’s empires began to collapse. Leaders who engaged in nation building in emerging states vilified certain groups, often referring to them as “national minorities,” and promulgated exclusionary policies toward actual or potential fifth columns. Campaigns of ethnic cleansing and forced population exchange resulted, including the Armenian genocide of the 1910s.

War and threats to territorial integrity heightened concerns over ethnic fifth columns during this period. The Soviet leader Joseph Stalin orchestrated the deportation of entire ethnic populations—including the Chechens, the Crimean Tatars, the Ingush, and the Meskhetian Turks—ostensibly to punish those who, in the words of Stalin’s chief of secret police, betrayed the Motherland, crossed over to the side of the fascist occupiers, [and] joined the ranks of saboteurs and spies.” Following the attack on Pearl Harbor, the U.S. government undertook the internment of over a hundred thousand Japanese Americans, despite the fact that intelligence reports at the time found no credible evidence of large-scale espionage or sabotage.

Ideology or ethnic, cultural, or religious identity can mark a group as distinct and suspect.

With the spread of communism and the intensification of Cold War competition, ethnically defined fifth columns gave way to ideologically defined ones. In the Soviet Union, which was racked by fears of “capitalist encirclement,” Stalin warned that his Western adversaries were acting through “wreckers, spies, saboteurs, and murderers.” In the United States, right-wing politicians accused government employees of secretly sympathizing with communism and the Soviet Union. The House Un-American Activities Committee, although initially created to defend against Nazi infiltration, was invigorated by investigations into the supposed communist sympathies of civil servants, leftist activists, and cultural figures. Loyalty oaths for public employees cemented the threat that fifth columns posed to national unity in the public’s mind.

With the end of the Cold War, the focus on ideology as a basis for fifth-column accusations waned and was superseded by renewed concern over ethnic and national loyalties. The breakup of the Soviet Union and of Yugoslavia left national minorities stranded in the midst of renewed efforts by national majorities to consolidate their “own” nation-states. Among them were the Russian-speaking populations in new post-Soviet states, who were feared as a potential cat’s paw for Russian irredentist claims. Krajina Serbs in Croatia were similarly depicted as fifth-column sympathizers of the Serbian leader Slobodan Milosevic based on their ethnicity, even though most of them did not share his views at the time.

This phase of ethnically driven fifth-column politics was also evident in Asia. After Uyghur protesters demanded the cessation of the mass immigration of Han Chinese into Xinjiang Province in 1990, China cracked down on protesters and began painting the Uyghurs as an ethnic and religious nationalist threat. That framing has survived to the present, as China has portrayed political violence in Xinjiang as a product of subversive infiltration by transnational jihadi networks.


Today, fifth-column politics is omnipresent. The end of the United States’ “unipolar moment,” coupled with the rising aspirations of revisionist states, has increased geopolitical instability. Russia has been a major source of this instability, invading Georgia in 2008 and Ukraine twice, ostensibly on behalf of Russian-speaking separatists or supposedly oppressed populations. Other regional powers, such as Brazil, China, India, Iran, Japan, Saudi Arabia, South Africa, and Turkey, have also sought to exert influence within unstable regional orders.

Often, a sponsor country will support a friendly nationalist or ethnic group in an adjacent country that aspires for self-determination or autonomy. In response, politicians in the targeted country may play up the linkages between these alleged fifth columns and their foreign backers, seeking to generate support from the national majority. Such dynamics have been evident in the fraught politics surrounding actual or suspected Iranian support for the Houthis in Yemen, Saudi support for Sunni militants in Syria, and Chinese support for “fifth-column units” in Taiwan.

Regional powers also use fifth-column politics to cultivate local support in strategically important countries. Western politicians have accused Russia of supporting ideological allies in several democratic states and China of similarly buying the loyalty of politicians in Australia, Canada, and the United States. Earlier this year, U.S. FBI Director Christopher Wray warned that elected officials in the United States who are pro-China will “be called on to do Beijing’s bidding when their power and influence grow.” Status-quo powers, including the United States, engage in similar activities by supporting pro-Western movements around the globe.


Leaders have also used fifth-column appeals to capitalize on rising domestic ethnonationalism. Right-wing politicians often play on ethnic and cultural resentments, using the specter of disloyalty of particular domestic groups as the basis for populist political movements. Hungarian Prime Minister Viktor Orban exemplified this approach when he portrayed the financier and philanthropist George Soros as the leader of a fifth column in campaigns that played on anti-Semitic stereotypes. Other far-right politicians and parties in Europe have depicted Muslim citizens as threats to Christian civilization, and conservative politicians in the United States have used similar rhetoric in relation to Muslim Americans. Populist appeals that have succeeded in one country have been readily adopted by politicians in others, responding to similar anti-elite sentiments and cultural grievances.

Beyond ideological and ethnic criteria, fifth-column rhetoric also targets groups based on new forms of difference. Homosexuality has increasingly been linked to the infiltration of Western values, and LGBTQ identity has been seen as a form of fifth-column activity. In Poland, the ruling Law and Justice party’s presidential candidate compared what he called “LGBT ideology” to communism, and in China, gay people have been labeled “agents of foreign influence.”

Right-wing politicians play on ethnic and cultural resentments as the basis for populist movements.

Yet another framing for fifth-column accusations is the supposed fealty of politicians to supranational institutions at the expense of national interests. In the wake of the 2008 financial crisis, opposition parties and movements in Europe saw an opportunity to delegitimize the ruling parties that were willing to negotiate loan agreements with external actors such as the International Monetary Fund. Accusations of disloyalty were articulated by both left- and right-leaning populist movements. And they went beyond dividing society into “pure” patriotic citizens and a “corrupt” elite, as populist movements often do, successfully linking that elite to specific, presumably malevolent, external actors such as the IMF, Germany, and the European Union.

It was on these grounds that former Greek Prime Minister Alexis Tsipras attacked parties that had voted for two bailout agreements and other austerity policies before his Coalition of the Radical Left came to power: “We should never forget that the enemy is not just in Berlin, Brussels or Washington. The enemy, maybe the harshest one, is also within our borders,” he said in a speech in 2015. Such fiery allegations had lost their force by the end of his term as prime minister in 2019, especially after his coalition voted for a third bailout agreement. But the notion that political elites had colluded with the European Commission in Brussels or the IMF in Washington, turning Greece into a “debt colony,” as prominent members of Tsipras’s party put it, continued to be articulated by parties on both the left and the right. Fifth-column accusations linking domestic elites to “globalists” and international finance, often with anti-Semitic overtones, outlasted the financial crisis and have buoyed populist politicians around the world.


The diffusion of ideas around the world was once thought to benefit democracy, as movements and leaders emulated pro-democratic successes occurring elsewhere. But the primary beneficiaries of this learning process in recent years appear to be populist, ethnonationalist, and authoritarian forces. Strongmen such as Putin, Erdogan, and Orban have shown how employing fifth-column rhetoric can produce electoral success and unify majoritarian coalitions around perceived cultural and security threats. Such appeals have spread far and wide, in part thanks to social media. It is little wonder that parties in long-standing democracies have adopted similar tactics. Far-right parties in France depict Islam and Muslims as an existential threat to the French way of life. In the United States, the so-called replacement theory, which posits that elites (often specifically, Jews) deliberately promote immigration from the “Global South” to dilute the political power of white Americans, has proliferated on the right and appears to be increasingly mainstream. More recently, bipartisan China bashing in the United States threatens to unfairly target students, scholars, and scientists of Chinese ancestry.

Such rhetoric is likely to flourish in the coming election cycles. Needless to say, it will have important policy implications. Domestically, the feared presence of fifth columns could further erode trust between various ethnic, social, and partisan groups, amplifying polarization and undermining national cohesion. Where such claims become widespread, societies are likely to become more fragile, vulnerable to external meddling, and prone to violence.

Internationally, the belief that some countries seek to aid or “activate” friendly foreign groups to undermine their adversaries can become a self-fulfilling prophecy, pushing persecuted groups to seek external protection from their own governments. Overly solicitous rhetoric or actual support by external actors for supposed fifth columns can heighten the perceived threat in targeted countries, increasing the likelihood of interstate conflict. In the extreme, the reciprocal abuse of vulnerable groups by warring countries can lead to ethnic cleansing, as it did in Greece and Turkey at the beginning of last century and in Bosnia and Serbia at the end of it.       


If current trends continue, fifth-column politics will become a defining feature of geopolitics and diplomacy as well as domestic politics. Scholars and conflict resolution practitioners must learn to recognize the signs of campaigns against purported fifth columns when they appear and understand how internal polarization and international security crises can converge with dire consequences. And just as cynical politicians understand that accusing marginalized groups of disloyalty can initiate a cycle of alienation and aggression, well-intentioned policymakers must be cognizant of how their own rhetoric about security may inadvertently exacerbate suspicions toward unassimilated or ostracized populations. 

International organizations should put in place early warning systems tracking fifth-column accusations and cultivate relationships with local civil society groups. Discourse or policies that seek to stoke fifth-column tensions should spur international collective action in the form of shaming or sanctions. Insofar as inflammatory political rhetoric is intended to provoke a reaction from an accused fifth column, exposing this strategy and pushing back against these narratives through local media campaigns may make such provocations easier to resist.  

The forces driving fifth-column politics, however, are powerful and will not subside until political polarization, income inequality, and disinformation enabled by social media abate—none of which is likely to happen any time soon. In an age of uncertainty and fragmentation, fifth columns will no longer be confined to the dark corners of the nationalist imagination. They will be front and center in domestic and global politics.

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  • HARRIS MYLONAS is Associate Professor of Political Science and International Affairs at George Washington University’s Elliott School of International Affairs and Editor in Chief of Nationalities Papers.
  • SCOTT RADNITZ is Herbert J. Ellison Professor of Russian and Eurasian Studies in the Jackson School of International Studies at the University of Washington. From 2022 to 2023, he is Jean Monnet Fellow at the European University Institute in Florence, Italy.
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