Conventional warfare

The state was first advocated by Plato, then found more acceptance in the consolidation of power under the Roman Catholic Church. European monarchs then gained power as the Catholic Church was stripped of temporal power and was replaced by the divine right of kings. In 1648, the powers of Europe signed the Treaty of Westphalia which ended the religious violence for purely political governance and outlook, signifying the birth of the modern 'state'.

Within this statist paradigm, only the state and its appointed representatives were allowed to bear arms and enter into war. In fact, war was only understood as a conflict between sovereign states. Kings strengthened this idea and gave it the force of law. Whereas previously any noble could start a war, the monarchs of Europe of necessity consolidated military power in response to the Napoleonic war.

Prussia was one country attempting to amass military power. Carl von Clausewitz, one of Prussia's officers, wrote On War, a work rooted solely in the world of the state. All other forms of intrastate conflict, such as rebellion, are not accounted for because in theoretical terms, Clausewitz could not account for warfare before the state. However, near the end of his life, Clausewitz grew increasingly aware of the importance of non-state military actors. This is revealed in his conceptions of "the people in arms" which he noted arose from the same social and political sources as traditional inter-state warfare.[1]

Practices such as raiding or blood feuds were then labeled criminal activities and stripped of legitimacy. This war paradigm reflected the view of most of the modernized world at the beginning of the 21st century, as verified by examination of the conventional armies of the time: large, high maintenance, technologically advanced armies designed to compete against similarly designed forces.

Clausewitz also forwarded the issue of casus belli. While previous wars were fought for social, religious, or even cultural reasons, Clausewitz taught that war is merely "a continuation of politics by other means." It is a rational calculation in which states fight for their interests (whether they are economic, security-related, or otherwise) once normal discourse has broken down.

The majority of modern wars have been conducted using the means of conventional means. Confirmed use of biological warfare by a nation state has not occurred since 1945, and chemical warfare has been used only a few times (the latest known confrontation in which it was utilized being the Syrian Civil War). Nuclear warfare has only occurred once with the United States bombing the Japanese cities of Hiroshima and Nagasaki in August 1945.

The state and Clausewitzian principles peaked in the World Wars of the 20th century, but also laid the groundwork for their dilapidation due to nuclear proliferation. During the Cold War, the superpowers sought to avoid open conflict between their respective forces, as both sides recognized that such a clash could very easily escalate, and quickly involve nuclear weapons. Instead, the superpowers fought each other through their involvement in proxy wars, military buildups, and diplomatic standoffs. Thus, no two nuclear powers have yet fought a conventional war directly, with the exception of two brief skirmishes between, China and Russia in the 1969 Sino-Soviet conflict and between India and Pakistan in the 1999 Kargil War.

However, conventional wars have been fought since 1945 between countries without nuclear weapons, such as the Iran–Iraq War and Eritrean–Ethiopian War, or between a nuclear state and a weaker non-nuclear state, like the Gulf War and Russo-Ukrainian War.