The European Union (EU) faces a high-level security threat by the uncontrolled spread of disinformation and conspiracy theories, which has led to a significant increase in political extremism, anti-expert discourses, and increasing authoritarianism. This project explores disinformation campaigns in relation to (1) far- and extreme right radicalization strategies, (2) disinformation related to climate change, specifically ecofascism and (3) information warfare. Drawing on Systemic Functional Linguistics (SFL), corpus linguistics, forensic linguistics, Legitimation Code Theory (LCT) and open-source intelligence (OSINT), this project employs both quantitative and qualitative methods in a multidisciplinary approach to explore the linguistic construction of disinformation tactics, focusing specifically on dis/alignment, attitudes, values, emotions, moral judgements and criminogenic intent in radicalisation strategies and disinformation campaigns. Tactics within strategic narratives of disinformation campaigns were found to rely on the linguistic resources of attitude, persuasion, amplification and obligation. Specifically, linguistic markers of ecofascist rhetoric include branding non-white populations as ‘invading foreigners’ and ‘parasites’ and local minorities as ‘foreign species’. Disinformation tactics in information warfare were studied in the context of Russia’s invasion of Ukraine and its links to far- and extreme right radicalization. Findings reveal that such tactics are deployed in order to lay the groundwork for military intervention: in Syria, to justify Russian presence by claiming to fight ‘international terrorism’, and in Ukraine, to fight ‘Nazis’ and ‘extremists’. Despite the threat disinformation poses, government and law enforcement agencies continue to approach this problem from a reactive information operations and cybersecurity perspective rather than a proactive educational perspective. Therefore, there is an urgent need to counter the effect of disinformation by integrating critical digital literacy and multimodal discourse studies into educational curricula.