This research will begin with the statement that war is a dangerous and tremendous evil which has put pressures on mankind throughout history. If we look back, we could see there has not been a single century or even decade free of wars and armed conflicts. However, the main question as to whether a nation has an obligation to go to war has not yet been answered. As this question is one that has disturbed many people from politicians and common citizens to clergy and ethicists, it now needs to be answered. Although this is a philosophical question which has different interpretations, this paper will attempt to summarize the basic assumptions in this field while presenting a personal view on this problem based on the thesis that a nation has an obligation to go to war if a situation threatens its existence as a unity, or if it threatens its security and national safety. It is possible to distinguish both the external and internal threats which can cause a nation to go to war. Every nation relies on its own “common sense” which means prudent and reasonable policy towards other nations through the lenses of its own security and safety. For every nation, it is “reasonable” to protect itself, it is ‘reasonable” to defend itself, it is “reasonable” to fight against poor governance, etc. If something is of primary importance for a nation, it becomes an obligation. In this case, “common sense” becomes an obligation of a nation to go to war, if something threatens its happiness....
War can be used by a nation as a defensible tool if a threat is inevitable and predictable.
This, of course, is one of the most bewildering and disturbing aspects of today's wars, for those caught up in them no less than for those observing and trying to understand them. It's difficult to answer the question unambiguously, because each war is unique as it has different roots and causes. Nevertheless, all nations have the right to protect themselves before their innocent people will be injured. In this case, war can be a protection policy aimed at securing peace and happiness. For instance, although the war in Iraq has been claimed by the European community to be one of aggression towards the Iraqi people, from the point-of-view of the United States, it was a necessary step to protect its citizen from adverse intervention by a nation intending to use weapons of mass destruction.
An obligation of a nation go to war can be explained as an effort to reduce possible casualties and sufferings of the population which could be caused by foreign armed aggression.
In this situation, the obligation of a nation to go to war coincides with its strategy to survive as a unity, on the one hand, and with that of defending its national identity on the other. An obligation cannot be explained through a private (personal) interest of people taking part in a battle because a soldier or a general means nothing as a subject, but becomes simply a tool of the battlefield. Taking into account the United States and the war against terror, it's possible to say that an obligation of the nation to go to war concerns the questions of unity of the American nation and its existence. The