From Chapter 24 of Human Action by Ludwig von Mises:
Popular opinion sees the source of the conflicts which bring about the civil wars and international wars of our age in the collision of “economic” interests inherent in the market economy. Civil war is the rebellion of the “exploited” masses against the “exploiting” classes. Foreign war is the revolt of the “have-not” nations against those nations who have appropriated to themselves an unfair share of the earth’s natural resources and, with insatiable greed, want to snatch even more of this wealth destined for the use of all. He who in face of these facts speaks of the harmony of the rightly understood interests is either a moron or an infamous apologist of a manifestly unjust social order. No intelligent and honest man could fail to realize that there prevail today irreconcilable conflicts of material interests which can be settled only by recourse to arms.
It is certainly true that our age is full of conflicts which generate war. However, these conflicts do not spring from the operation of the unhampered market society. It may be permissible to call them economic conflicts because they concern that sphere of human life which is, in common speech, known as the sphere of economic activities. But it is a serious blunder to infer from this appellation that the source of these conflicts are conditions which develop within the frame of a market society. It is not capitalism that produces them, but precisely the anticapitalistic policies designed to check the functioning of capitalism. They are an outgrowth of the various governments’ interference with business, of trade and migration barriers and discrimination against foreign labor, foreign products, and foreign capital.
None of these conflicts could have emerged in an unhampered market economy. Imagine a world in which everybody were free to live and work as entrepreneur or as employee where he wanted and how he chose, and ask which of these conflicts could still exist. Imagine a world in which the principle of private ownership of the means of production is fully realized, in which there are no institutions hindering the mobility of capital, labor, and commodities, in which the laws, the courts, and the administrative officers do not discriminate against any individual or group of individuals, whether native or alien. Imagine a state of affairs in which governments are devoted exclusively to the task of protecting the individual’s life, health, and property against violent and fraudulent aggression. In such a world the frontiers are drawn on the maps, but they do not hinder anybody from the pursuit of what he thinks will make him more prosperous. No individual is interested in the expansion of the size of his nation’s territory, as he cannot derive any gain from such an aggrandizement. Conquest does not pay and war becomes obsolete.