Introduction

This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book addresses a pressing, empirical puzzle, which reflects debates, both enduring and contemporary, in the sub-discipline of International Security. It describes the problems in North Atlantic Treaty Organization's (NATO) conventional deterrence in the Baltic region. The book analyses NATO's nuclear deterrence posture that was the core of the alliance's deterrence posture during the Cold War. It also analyses developments in Sweden's defence policy before and after the beginning of the Ukraine crisis. The book describes the development of defence strategy from a historical perspective and revealing the changes that have taken place since the beginning of the Ukraine crisis. It illustrates that society is very vulnerable towards non-military threats, despite the fact that a Russian-speaking minority is not an issue in Lithuania. The book offers numerous insights into how various European countries have been responding to Russia's assertive policies since 2014.