Many scholars believe that adherence to political borders poses critical challenges for progress in the international system. Political borders have had a profound impact on how the international system operates. It is first of all important to understand how the modern international system came into being. Scholar Joseph Nye theorizes that there are three main types of word politics that have emerged over time. The imperial system and the feudal system describe how politics were organized historically, while an anarchic system of states characterizes the current global political landscape. This system was born out of the Treaty of Westphalia in the seventeenth century, which divided Europe into states. The politics of this system largely centered upon realism, a perspective that emphasizes power and the potential for conflict in pursuit of national interests. This system also largely revolved around the idea of sovereignty, as well as led to the development of nationalism among citizens of states.

Europe came to dominate the international system through technological advances during the Industrial Revolution and expansion of colonial empires. Preserving peace among European states hinged upon maintaining a balance of power. Two main alliances developed as a result: the Triple Alliance between Italy, Germany, and Austria-Hungry of 1882, and the Triple Entente of France, Great Britain, and Russia of 1907. Concurrently, scholars pushed for a more systematic study of political behavior, which led to the institutionalization of political science as a discipline. At this time, scholars promoted a new political philosophy that emphasizes cooperation among states called liberalism. Other scholars and politicians pushed this idea further by asserting that a peaceful world order could be established through cooperation. This view came to be known as idealism. However, the peace was shattered in the first part of the twentieth century as military expansion threatened sovereignty, economies destabilized, and two world wars broke out.

Emerging from World War II, two relatively equal centers of powers became the dominant players in a bipolar world: the United States and the Soviet Union. The struggle between the two states is known as the Cold War, as each power tried to assert their ideologies, morality, and political and economic influences. The United States’ general policy was that of containment, a strategy to limit Soviet aggression by establishing military alliances. The Cold War resulted in a series of moves and countermoves in an attempt to mold the international system, including the establishment of NATO and the Warsaw Pact, the Cuban Missile Crisis, and the Vietnam War. As pressures mounted, both powers attempted to lessen these confrontations through a policy called détente. The United States and the Soviet Union continued to engage each other until the Soviet Union fell in 1991.

After the dissolution of the Soviet Union, a new distribution of power emerged that caused conflicts in the Balkans, the Middle East, and Africa. Genocide, civil wars, and ethnic and religious-based conflict plagued African countries, such as Somalia, Rwanda, South Sudan, and the Central African Republic. The United States became increasingly active in the Middle East through wars in Afghanistan and Iraq, particularly after the terrorist attacks of September 11, 2001. Many citizens of countries in the Middle East have called for greater freedom through a series of prodemocracy revolutions known as the Arab Spring. This unrest led Syria, however, into a protracted and bloody civil war. Additionally, the Islamic State in Iraq and Syria (ISIS) further destabilized the region. China and Russia are both emerging as a new power and old power, respectively. China, with its significantly enhanced military capabilities, has asserted its geo-strategic interests by laying claim to island chains belonging to Vietnam and the Philippines, and Russia’s annexation of the Crimean peninsula in Ukraine signaled its intention to act unilaterally to support its vital strategic interests.

As a result of these ongoing events and the realignment of the world, political scientists have introduced a new way of thinking about the international system, constructivism, which posits that the state and the rules that govern it are artificial constructs. Along with realism and liberalism, these political philosophies offer different ways of conceptualizing the international system and the quest for security. These theoretical building blocks become critical as we face new challenges in crossing political borders.