War, yo.

To begin to define precisely what war actually is, one has to consider the many different components that make up a war. For one thing, there has to be armed conflict for a situation to be considered war. This does not mean that the armed conflict has to involve the international community; war can be internal as well. Two groups disagreeing on something like a particular plot of land, however, does not amount to a war unless a distinct level of violence has been reached. Aggression between two people is not war, and neither is a brutal fight between two neighborhoods. Organized violence at a larger scale, on the other hand, like between the Chadian government and rebel groups in the nation, is regarded as a true war. As Brian Orend from Stanford University said, “The conflict of arms must be actual, and not merely latent, for it to count as war. Further, the actual armed conflict must be both intentional and widespread: isolated clashes between rogue officers, or border patrols, do not count as actions of war. The onset of war requires a conscious commitment, and a significant mobilization, on the part of the belligerents in question. There's no real war, so to speak, until the fighters intend to go to war and until they do so with a heavy quantum of force”. In my opinion, something like the Cold War does not truly fall under the definition of term because there was never a violent clash between the military forces of the USSR and the US. If the two nations had actually used warfare against each other instead of just engaging in an arms race then the Cold War would have been quite appropriately named this.
Another part of the definition of war that is often debated is whether or not fighting against an idea constitutes as war. This has lead to the overuse of the term to describe issues that are not actually wars. To my knowledge, a war cannot just be fought against an idea; there has to be at least two opposing sides engaged in armed conflict. One example of the term being misused was when Lyndon Johnson coined the phrase “the War on Poverty” during his State of the Union address. Though poverty was a major issue that Johnson wanted to conquer, this was not, under any circumstances, a war. Proclaiming the struggle to solve the issue of poverty in the US a war puts it on the same level as a conflict where actual warfare is used and people are brutally killed by the hundreds, sometimes thousands. Fighting against an idea, especially without the use of force, should not be considered war in the first place. War does not have to be fought between two states, but it does have to be between two separate groups of people at the least.

Sources:
http://lawofwar.org/introduction.htm#Distinctions
http://plato.stanford.edu/entries/war/